[REVIEW REQUEST] RT-37039: Provide missing convenience constructors to controls classes

[Jonathan Giles]

Hi all,

One thing I'm keen to get into JavaFX is a few convenience constructors 
for UI controls, primarily related to varargs constructors for passing 
in things like a varargs of tabs into a TabPane, table columns into a 
TableView, etc. I've posted a patch of a few proposed improvements to 
RT-37039 [1], and both welcome your review and your suggestions on 
additional constructors that might be beneficial.

[1] https://javafx-jira.kenai.com/browse/RT-37039

Thanks,
-- Jonathan