Adds logic to read/set changelog version. Refs #4.
Moves other NSUserDefaults code to new file. Refs #4.
Adds basic tabbar badge mechanism. Refs #4.
Generates header with changelog version. Refs #4.
Adds changelog value resetting, fixes notification. Refs #4.
Adds external TDBadgedCell submodule. Refs #4.
Implements badge cell through custom subclass. Refs #4.
Documents task in changes log. Refs #4.
Adds TDBadgedCell license. Refs #4.
Merge branch 'feature/t4_implement_badges'