Improve interface consistency.
Add keyboard mapper to the instrument editor.
Add instrument control searching by instrument ID.
Add support for overriding selected insturment control.
Use control ID of the edited instrument in the instrument editor.
Fix indentation.
Add support for retrieving random typewriter button models.
Add instrument test button to the instrument editor.
Store active control ID information in session.
Rename UiManager to ControlManager.
Update old naming style.
Fix instrument test button behaviour when instrument control is not found.
Remove unnecessary caching code.
Merge pull request #273 from kagu/instrument_test

Instrument test