Removed private member from interface.
Fixed not being able to parse tags without values.
Updated documentation generator to use the new TypeScript API.
Added support for Map.size to SimpleMap
Added browser support for async tests and mocha's setup() function.
Implemented a mechanism for running tasks in a web worker.
Web worker support for calling libjass.parser.parse()
Added web worker test for libjass.parser.parse()
Web worker improvements.

- Don't restrict usage to only one worker channel per library instance.
- WorkerChannel.request() now returns a promise instead of needing a callback passed in.
Added support for interfaces to documentation generator.
Fixed min-width calculation to correctly sum horizontal margins.
Fixed typo.
Explicitly set text alignment on absolutely-positioned subs because they'll go in a .an0 <div> and so won't get alignment CSS text-align.
Nested rotations.