Merge pull request #143 from nilshartmann/master

Preparing for Blueprint API
~ minor fix to prevent a RuntimeException
~ added empty 'BundleMakerPropertyPage' as category for further property pages
~ clean-up
~ allow usage of project specific mvn settings
Merge remote-tracking branch 'origin/master'
~ moved 'Activator' from org/bundlemaker/core/ui/artifact/internal -> org/bundlemaker/core/ui/artifact
~ Fixed [BM-278]: [UI focus handling] After parsing a project the artifact tree has no focus
~ fixed default property settings
~ fixed default property settings
~ empty property page
~ set version to 0.9.0
~ clean up
Implemented Virtual Root as JDK Proxy