Add component size setters to AbstractQuery

* setSizeFull()
* setSizeUndefined()
* setWidth(String)
* setWidth(float, Unit)
* setHeight(String)
* setHeight(float, Unit)
Add sizing and visible/enabled/read-only tests
Allow Predicate<? super C> when filtering instead of exact match
Add human-readable methods in addition to $ shortcuts to VQuery
Add variadic constructor, addValidator, removeValidator to FieldQuery
Add more filtering tests
Rename isAlso(Class<?>) to is(Class<?>)