Commented out the Undo Whiteboard Mark line from Shortcut Help Window, since it is currently inactive.
Commented out the Focus Colour Picker line from Shortcut Help Window, since the Colour Picker component has been removed.
Commented out the Kick User line from Shortcut Help Window, since it is currently inactive.
Updated the keys used for certain hotkey functions.
Added global hotkey to mute all users but the Presenter.
Merge pull request #164 from SenecaCDOT-BigBlueButton/hotkey-cleanup

Hotkey cleanup