Toolbar and button bar unification

Currently have button farm. And will only have more buttons in the future.

• Will want a bundle_info.xml way of listing the buttons provided by a bundle
• May also want to be able to dynamically add/remove buttons?
• Need way to disable/enable buttons so the usable buttons can be context sensitive (eg., mouse modes)

Prototype with Roger Pincombe's ​Office 2010 Style Ribbon Toolbar in HTML/CSS/JS

• buttons are hardcoded into section
• remove text hints with context menu
• balloon help for icons
• have to patch to fix size/location/color of balloon help
• not updated since 2011 (except README.md)

Bugs / Enhancements

• section text that has letters with descenders have the descenders clipped
• want colors to match Qt UI elements
• icons should have transparent backgrounds
• hintless version should resize to lower height
• should hintless version (optionally?) have 2 rows of smaller buttons?