Little workaround on AbsoluteLayout

This solves the issue #218 . I tested it on Nifty-Editor and i didn't
notice any bugs .
Also height and width

i don't know if this is a real user case... it is only to be coherent
with the other commit .
Solve an error in the comment at line 64 

Evil cut&paste :D
Merge pull request #219 from relu91/1.4

Solve issue #218