Merge pull request #69 from rnc/master

Configure metadata plugin
Only inject source/metadata plugins at execution root. This avoids multiple injections in repositories that don't have parent standard relationships
Issue 52 : Handle strict alignment for properties. Don't align non-matching in strict mode.
Issue 63 : Only run ProjectSourcesInjectingManipulator if at least one other manipulator is active. Add docs for build-metadata-plugin.