can unselect spaces and descriptions by clicking them
Merge branch 'refactor'
Merge branch 'master' of github.com:IMDC/LiveDescribe-Desktop into valdev

Conflicts:
	LiveDescribe/LiveDescribe/View/MainWindow.xaml.cs
Reduce Volume when playing a Regular Description
Add Find Spaces Menu Item
Refactor Commands

Commands are defined as ICommands now. Command functionality has been
placed in constructor of class as lambdas. To call a command in-class,
use Command.Execute()
Add Waveform class
Refactor AudioUtility

Move FindSpace functionality into separate class, AudioAnalyzer.
Refactor Description