Ramping up to 8.0-r2

[tbeernot]

The JavaOne is always a good moment to release a new version of a library, so I've scheduled to release JFXtras 8.0-r2 a week prior to the J1, on september 20th. In ramping up that date I've just now moved Circular layout from Labs over to JFXtras common, and the circular menus to a new component "jfxtras-menu". They are as of now included in jfxtras-8.0-r2-SNAPSHOT instead of jfxtras-labs.

Regards,

Tom