Some small improvements to sbt-pack in my fork

[DavidPerezIngeniero]

My need:

To copy *.jar of a webapp called myproject to WEB-INF/lib

The pack task doesn't work because it creates a bin and a lib folders, and other stuff.

I've created a task called packCopyDependencies.
For faster processing and save disk space, I've created a packUseSymbolicLinks, that creates symbolic links instead of copying.

As I want to copy all the dependencies of myproject, but not myproject.jar, I've created the property packExcludeLibJars setting. The original packExclude settings controls both the dependencies of a project and the project.jar. That provides less flexibility.

Luckily, as the code is clean and easy to understand, my modifications have been easy to make.

https://github.com/DavidPerezIngeniero/sbt-pack/blob/develop/src/main/scala/xerial/sbt/Pack.scala

I'll try to correct a previous problem with the checkDuplicatedDependencies task, and make a pull request of all my changes.

[xerial]

ok. If possible please make a separate pull request for each change for excluding project.jar and duplicate check.

[DavidPerezIngeniero]

Sorry, I don't know how to make separate pull requests, and I prefer to spend my limited time to write tests.

[DavidPerezIngeniero]

I've made the pull request.