Refactor: Changed all invocations of removeX to setX(null)
Refactor: Changed all invocations of getXCount to getX.size
Refactor: Changed all invocations of getXSet to getX
Refactor: Changed all invocations of hasX() to getX().contains
Last API Fixes.
Refactor: Changed invocations of 'getXpto' to 'getXptoSet'
Added Deprecated getXpto domain methods.