FLOE-135: keyboard nav for controls buttons

Added the bold, italic, and underline controls to the tab order and made them keyboard activatable.
FLOE-135: Added keyboard shortcuts

Added the keyboard short cuts for the bold, italic, and underline controls. They use the standard short cut combinations including using ctrl for windows and command for mac.
Merge branch 'master' into FLOE-135
FLOE-135: Switched progressive checking strategy

Switched to use progressiveCheckerForComponents strategy for switching between mac and pc keyboard shortcuts.
Merge remote-tracking branch 'justin/FLOE-135'

* justin/FLOE-135:
  FLOE-135: Switched progressive checking strategy
  FLOE-135: Added keyboard shortcuts
  FLOE-135: keyboard nav for controls buttons
FLOE-164: Separated the simple editor and the metadata panel.
FLOE-164: Code improvement and styling fix.
FLOE-164: Refactored code to better modularize metadata and simple editor. It includes: 1. moved the video grade component "fluid.metadata.videoMetadataPanel" for defining video metadata and the general wrapper component "fluid.metadata.metadata" for media grade components into metadata source code directory rather than having them in demos code, as well as completing unit tests for them; 2. kept the save metadata functionality in demos.
FLOE-164: Use the namespace demo.metadata for instantiating metadata demo.
FLOE-164: Add the line to initialize the "demo" variable.
FLOE-164: Changed the variable scope of the "demo" variable.
Merge remote-tracking branch 'cindy/FLOE-164'

* cindy/FLOE-164:
  FLOE-164: Changed the variable scope of the "demo" variable.
  FLOE-164: Add the line to initialize the "demo" variable.
  FLOE-164: Use the namespace demo.metadata for instantiating metadata demo.
  FLOE-164: Refactored code to better modularize metadata and simple editor. It includes: 1. moved the video grade component "fluid.metadata.videoMetadataPanel" for defining video metadata and the general wrapper component "fluid.metadata.metadata" for media grade components into metadata source code directory rather than having them in demos code, as well as completing unit tests for them; 2. kept the save metadata functionality in demos.
  FLOE-164: Code improvement and styling fix.
  FLOE-164: Separated the simple editor and the metadata panel.
Merge branch 'master' into FLOE-116

Conflicts:
	demos/html/metadata.html
	tests/all-tests.html
FLOE-116: Fixed the issue that changes made in captions panel are not saved.