Add missing CSS style types for IModelDecorationOptions

[hawkerm]

There are some other CSS Stlyes not currently strongly-typed (or supported as part of the CssStyleBroker) in IModelDecorationOptions.

May also want to see if we can use a factory pattern to help construct styles more easily???

[hawkerm]

Moved CssStyleBroker part to its own Issue #42.

Also, guessing I may not get to this for the next release, but should at least hide the ones that aren't hooked into the Broker as they won't do anything anyways...