Update release doc and related script (apache#1252)

* Adjust release doc and script based on last release vote.

* Update UI declaimer file.

* Update create_source_release.sh

* Update How-to-release.md

DISCLAIMER

@@ -1,4 +1,4 @@
-Apache SkyWalking (incubating) is an effort undergoing incubation at The Apache Software Foundation (ASF), sponsored by Incubator. 
+Apache SkyWalking (incubating) is an effort undergoing incubation at The Apache Software Foundation (ASF), sponsored by the Apache Incubator PMC.
 Incubation is required of all newly accepted projects until a further review indicates 
 that the infrastructure, communications, and decision making process have stabilized in a manner consistent with other successful ASF projects. 
 While incubation status is not necessarily a reflection of the completeness or stability of the code, 

docs/en/How-to-release.md

@@ -49,10 +49,13 @@ The release will automatically be inserted into a temporary staging repository f
 ```shell
 switch to release version tag
 export RELEASE_VERSION=x.y.z (example: RELEASE_VERSION=5.0.0-alpha)
+export RELEASE_ROUND=1 (example: RELEASE_ROUND=1)
 cd tools/releasing
 sh create_source_release.sh
 ```
 
+`x` in `RCx` is based the number of attempts release, and starts with 1.
+
 The `apache-skywalking-apm-incubating-x.y.z-src.tgz` should be found in `tools/releasing` folder,
 with .asc, .sha512, .md5
 
@@ -67,7 +70,7 @@ with .asc, .sha512, .md5
 
 ## Upload to Apache svn
 1. Use ApacheId to login `https://dist.apache.org/repos/dist/dev/incubator/skywalking/`
-1. Create folder, named by release version
+1. Create folder, named by release version and round, such as: x.y.z(RCx)
 1. Upload Source code package to the folder with .asc, .sha512
     * Package name: apache-skywalking-incubating-x.y.z-src.tar.gz
     * See Section "Build and sign the source code package" for more details 
@@ -97,18 +100,25 @@ Release notes:
 Release Candidate:
 
  * https://dist.apache.org/repos/dist/dev/incubator/skywalking/xxxx
+ * sha512 checksums
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x-src.tgz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.tar.gz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.zip
 
 Maven 2 staging repository:
 
  * https://repository.apache.org/content/repositories/xxxx/org/apache/skywalking/
 
 Release Tag :
 
- * (Git Tag)
+ * (Git Tag) x.y.z(RCx)
 
 Release CommitID :
 
- * (Git Commit ID)
+ * https://github.com/apache/incubator-skywalking/tree/(Git Commit ID)
+ * Git submodule
+   * skywalking-ui: https://github.com/apache/incubator-skywalking-ui/tree/(Git Commit ID)
+   * apm-protocol/apm-network/src/main/proto: https://github.com/apache/incubator-skywalking-data-collect-protocol/tree/(Git Commit ID)
 
 Keys to verify the Release Candidate :
 
@@ -143,18 +153,25 @@ Release notes:
 Release Candidate:
 
  * https://dist.apache.org/repos/dist/dev/incubator/skywalking/xxxx
+ * sha512 checksums
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x-src.tgz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.tar.gz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.zip
 
 Maven 2 staging repository:
 
  * https://repository.apache.org/content/repositories/xxxx/org/apache/skywalking/
 
 Release Tag :
 
- * (Git Tag)
+ * (Git Tag) x.y.z(RCx)
 
 Release CommitID :
 
- * (Git Commit ID)
+ * https://github.com/apache/incubator-skywalking/tree/(Git Commit ID)
+ * Git submodule
+   * skywalking-ui: https://github.com/apache/incubator-skywalking-ui/tree/(Git Commit ID)
+   * apm-protocol/apm-network/src/main/proto: https://github.com/apache/incubator-skywalking-data-collect-protocol/tree/(Git Commit ID)
 
 Keys to verify the Release Candidate :
 
@@ -218,18 +235,25 @@ Release notes:
 Release Candidate:
 
  * https://dist.apache.org/repos/dist/dev/incubator/skywalking/xxxx
+ * sha512 checksums
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x-src.tgz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.tar.gz
+   - sha512xxxxyyyzzz apache-skywalking-apm-incubating-x.x.x.zip
 
 Maven 2 staging repository:
 
  * https://repository.apache.org/content/repositories/xxxx/org/apache/skywalking/
 
 Release Tag :
 
- * (Git Tag)
+ * (Git Tag) x.y.z(RCx)
 
 Release CommitID :
 
- * (Git Commit ID)
+ * https://github.com/apache/incubator-skywalking/tree/(Git Commit ID)
+ * Git submodule
+   * skywalking-ui: https://github.com/apache/incubator-skywalking-ui/tree/(Git Commit ID)
+   * apm-protocol/apm-network/src/main/proto: https://github.com/apache/incubator-skywalking-data-collect-protocol/tree/(Git Commit ID)
 
 Keys to verify the Release Candidate :
 
@@ -272,7 +296,7 @@ I will procedd to publish the release and send ANNOUNCE.
 1. Move source codes tar balls and distributions to `https://dist.apache.org/repos/dist/release/incubator/skywalking/`.
 ```
 > export SVN_EDITOR=vim
-> svn mv https://dist.apache.org/repos/dist/dev/incubator/skywalking/5.0.0-alpha https://dist.apache.org/repos/dist/release/incubator/skywalking
+> svn mv https://dist.apache.org/repos/dist/dev/incubator/skywalking/x.y.z(RCx) https://dist.apache.org/repos/dist/release/incubator/skywalking
 ....
 enter your apache password
 ....
@@ -281,6 +305,7 @@ enter your apache password
 2. Do release in nexus staging repo.
 3. Public download URLs under `http://www.apache.org/dyn/closer.cgi/incubator/skywalking/x.y.z`.
 4. Public KEYS, sigs and sha512 URLs under `https://www.apache.org/dist/incubator/skywalking/xxxx`
+5. Re-tag on GitHub, tag `x.y.z(RCx)` as `x.y.z`, and publish a GitHub release based on this tag.
 5. Send ANNOUNCE mail to `[email protected]`.
 ```
 Mail title: [ANNOUNCE] Release Apache SkyWalking (incubating) version x.y.z
@@ -321,3 +346,5 @@ projects. While incubation status is not necessarily a reflection
 of the completeness or stability of the code, it does indicate
 that the project has yet to be fully endorsed by the ASF.
 ```
+
+6. Update skywalking website download page: http://skywalking.apache.org/downloads/

tools/releasing/create_source_release.sh

@@ -20,11 +20,13 @@
 # This script relies on few environment variables to determine source code package
 # behavior, those variables are:
 #   RELEASE_VERSION -- The version of this source package.
+#   RELEASE_ROUND -- The round of this version release.
 # For example: RELEASE_VERSION=5.0.0-alpha
+#              RELEASE_ROUND=1
 
 
 RELEASE_VERSION=${RELEASE_VERSION}
-TAG_NAME="v"${RELEASE_VERSION}
+TAG_NAME=${RELEASE_VERSION}(RC${RELEASE_ROUND})
 PRODUCT_NAME="apache-skywalking-apm-incubating"
 
 echo "Release version "${RELEASE_VERSION}
@@ -36,6 +38,12 @@ if [ "$RELEASE_VERSION" == "" ]; then
   exit 1
 fi
 
+if [ "$RELEASE_ROUND" == "" ]; then
+  echo "RELEASE_ROUND environment variable not found, Please setting the RELEASE_ROUND."
+  echo "For example: export RELEASE_ROUND=1"
+  exit 1
+fi
+
 echo "Creating source package"
 
 PRODUCT_NAME=${PRODUCT_NAME}-${RELEASE_VERSION}
@@ -68,4 +76,4 @@ tar czf ${PRODUCT_NAME}-src.tgz \
 
 gpg --armor --detach-sig ${PRODUCT_NAME}-src.tgz
 
-shasum -a 512 ${PRODUCT_NAME}-src.tgz > ${PRODUCT_NAME}-src.tgz.sha512
+shasum -a 512 ${PRODUCT_NAME}-src.tgz > ${PRODUCT_NAME}-src.tgz.sha512