More skin system improvements; Create a new BaseTemplate class extended from QuickTem...

More skin system improvements; Create a new BaseTemplate class extended from QuickTemplate, this class will house helper methods that interact with QuickTemplate data set by SkinTemplate to help cut down on boilerplate for common uses of that data.
For the first helper in this class add a helper to use in generating a toolbox. Include a list item and link generating method that can be used to generate most of our sidebar links with minimal code.
Eventually this toolbox code will be used in code abstracting common sidebar generating code away into common helpers. For now make MonoBook and Vector and the skins based off of them use this method of generating toolboxes and sidebar links.