Template dialog cleanup

Objectives:

* Break template page creation into it's own method
* Get rid of styling being applied in JavaScript
* Fix styling issues

Changes:

ve.ui.MWTemplateDialog.js
* Add method for adding a template page
* Replace css calls with addition of classes for styling
* Cleanup of append calls

ve.ui.Dialog.css
* Make inputs in the template dialog full width and a reasonable height

ve.ui.Widget.css
* Swap margins with padding in labels to prevent layout issues
* Prevent textareas from being resized in safari/chrome

Change-Id: I4030d8605aad865251ecd0aeb8cc72d333bed6a4