Add initial implementation of sound effects feature

Adds a sound effect player class which listens for the following events from the voice recognizer:
- Command Accepted
- Command Rejected
- Listening Started
- Listening Stopped

Sound file locations are currently hard-coded and only WAV files are supported (due to the use of System.Media.SoundPlayer).
The people demand Spanish

Thanks to Dj Octacon (Falcata) for this contribution.
Display localized translation names in languages window
Fix translation selection on first run
Fixes #60
Add sound effect UI and clean up initial implementation.
Merge branch 'development' of https://github.com/flyingcroissant/articulate into feature/soundeffects

Conflicts:
	Articulate/MainWindow.xaml.cs

Merge in changes since creating feature branch.
Remove unused method.
The French have arrived

Thanks to @Wismerheal for the translation file
Tweaks for French translation

Fixes some file format issues and UI layout for some buttons with long
translations.
Allow key press delays to be adjusted
Initial de, es, fr translations for key press delays

Needs translation of the explanations
Merge remote-tracking branch 'flyingcroissant/feature/soundeffects' into development
Code style changes for MainWindow
Version bump to v0.2.4