queue.push callback is optional
jQuery: Modified some functions variable types

Updated the jQuery definitions file, modifying removeAttr, removeClass,
removeProp, toggleClass and on functions to appropriately use string
rather than any, which aligns it with the jQuery API docs.
Merge pull request #1160 from halfninja/patch-1

queue.push callback is optional
Merge pull request #1161 from JoshStrobl/master

jQuery: Modified some functions variable types