Added new tag related tables to database
Added data access classes for new Tags API
Updated tag DTO classes and added correspinding add() methods to SleuthkitCase
Tweaked design of new tags API DTOs and db tables
Filled out database and DTO code for new tags API
Merge branch 'new_tags_api', remote-tracking branch 'upstream/master' into new_tags_api
Merge remote-tracking branch 'upstream/master' into new_tags_api
Improved robustness of new tag API DTOs
Merge remote-tracking branch 'upstream/master' into new_tags_api
Fixed Tags class bug
Merge branches 'master' and 'new_tags_api'