Merge pull request #10 from jgodi/master

Fixing some showcase issues and putting the project back onto GWT 2.5.1 until 2.6 is fully released.
Added GitHub ribbon to demo (issue #9)
Make GitHub ribbon fixed
Updated Bootstrap to version 3.0.3 (issue #6)
Minor fixes in demo
Corrected wrongly merged <scm> values
[maven-release-plugin] prepare release 0.3
[maven-release-plugin] prepare for next development iteration
Update README.md
Added BuildHive build status to README
Allowing widgets inside the Panel Header, if user sets a Heading then give it the right style.