[jquery.byteLimit] Set vars in return this.each loop

[jquery.byteLimit] Set vars in return this.each loop
* Set vars in return this.each loop. This is the defacto standard plugin structure
  but somehow it slipped through this one (it's a 2 line wrapper, easy to miss).
* Added unit test (which failed before this commit)
* Fixes:
-- (bug 35294) jquery.byteLimit shouldn't set element specific variables outside the "return this.each" loop.