refs #20
refs #20

In "Ada Project Explorer", only projects with Ada nature are shown.
Merge branch 'master' of local repository into navigator_view

Conflicts:
	org.padacore.ui/plugin.xml
Merge branch 'master' of local repository into navigator_view

Conflicts:
	org.padacore.ui/META-INF/MANIFEST.MF
Through hell with manifests.
refs #20

Files and folders are now properly displayed.
refs #20

User can now choose which file extensions to display in project
explorer.