Button related changes + PSR-2

1) Remove deprecated comments
2) Now you can pass options to View_Popover class in addPopover
3) Now you can configure used CSS classes more easily

addMenu() changes:
4) you can pass options to Menu class
5) sets button CSS class (ui-state-highlight) when menu is active (visible)
6) removed width=200px parameter - this shouldn't be the way to define width. Use CSS or set width using menu class options. Default width Chrome sets works quite fine too btw.
7) menu will be closed (toggle) when you click on button more than once
8) replaced javascript defined as string with appropriate methods in addMenu

9) Some fixes in ButtonMenuButton and DropButton

10) PSR-2

Notes:
- I believe that ButtonMenuButton can now be dropped because its functionality is moved to new Button->addMenu class