Fixed source compatibility with Scala IDE master

Source compatibility with master was broken by this recent commit
scalaide/scalaide@cf73ce8. Furthermore, this patch depends on
https://github.com/scala-ide/scala-ide/pull/571
Merge pull request #196 from dotta/issue/update-code-to-compile-against-ide-master

Fixed source compatibility with Scala IDE master
Merge pull request #195 from dragos/issue/bump-plugin-profiles

Bump to the new plugin-profiles version.
Switch to plain Scala OSGi bundles.