0.99.0

Merged pull requests and fixed issues:

#19 - Update to use jgit rather than calling out to git (fixes issue #18 - Out of memory when running in travis)
#17 - Version of plugin
#15 - Better handling for coveralls.io 500 response
#14 - Updated Specifying Your Repo Token
#12 - Doesn't send folder info for sub projects
#10 - Updated Readme with build.scala example
#9 - Moved CoverallsPlugin to enable import from Build.scala projects
#6 - coveralls.io internal server error handling