More work on refactoring fragments and dialogs to be more abstract and modular.

Tags, Children, Facts, Comments, use a unified AddEdit framework for dialogs, Images uses the Edit part of the framework. Locations and URLs instigate activities for editing and unique dialogs for adding so don't fit into this set up. Added ConfigAddEditActivity to define appropriate classes for aforementioned data that use this framework. Removed old versions of DialogTagAddFragment, DialogTagEditFragment etc. as now defined using one line in ConfigAddEditActivity.