Remove index.properties in GerritManagement

All contents in index.properties for GerritManagement has never been
used. So it can be removed.
Move properties for GerritManagement to GerritServer

Almost resources for GerritManagement was moved to GerritServer.
So language resources should be moved.
Add marker to added string resources
Merge pull request #82 from rinrinne/cleanup-resource

Cleanup resources