[GAE Server] Deleting Vote, FollowUp and Flag when user delete an Anno
Merge branch 'develop' of github.com:usersource/anno into develop
[Anno App] Minor fixes related to editable invitation contact
[GAE Server] Added TagApi in services
[GAE Server] Finding and inserting hashtags in database from followup when user insert a followup
[GAE Server] Updated migration schema for adding hashtags in database from existing annos and followups