[skip travis] improve docs

CONTRIBUTING.md

@@ -0,0 +1,24 @@
+# Contributing
+First off, thanks for taking the time to contribute! Feel free to make Pull Request with you changes.
+
+
+# Requirements
+
+Go >= 1.11
+Ruby >= 2.x
+
+# Proccess
+
+1. Fork repo
+2. git clone <forked_repo>
+3. run commands:
+```bash
+go build
+bundle install
+```
+4. Make changes
+6. Test it
+```bash
+bundle exec rspec spec/
+```
+7. Push your changes in repo

README.md

@@ -184,6 +184,14 @@ hookah install
 ```
 Hookah wiil read existed hook groups and reproduce hooks in `.git/hooks` directory.
 
+### How can I can skip hoookah execution?
+
+We have env HOOKAH=0 for that
+
+```bash
+HOOKAH=0 git commit -am "Hookah skipped"
+```
+
 ### How can I run my linter against only modified files?
 
 No problem. Lets take `rubocop` linter for ruby as example:
@@ -227,6 +235,18 @@ func main() {
 ```
 We include context package only for convenience. It`s just few useful functions.
 
+### Some hooks proved ARGS from git. How can I capture it in my script?
+For pure script you can do it like that:
+
+Example for `prepare-commit-msg` hook:
+```bash
+COMMIT_MSG_FILE=$1
+COMMIT_SOURCE=$2
+SHA1=$3
+
+# ...
+```
+
 ### Uninstall
 
 ```bash