[New Feature] Add buttons, checkboxes and seekbars to change signal's levels when in DEBUG_MODE

[GoogleCodeExporter]

Add buttons, checkboxes and seekbars to change signal's levels when in 
DEBUG_MODE.

Both debug signals must be configured, i.e., there must be a way to change 
their frequencies and levels.

Original issue reported on code.google.com by zz4...@gmail.com on 3 Feb 2012 at 6:08