Funcube Dongle controller

 Controller application for the Funcube Dongle software defined radio receiver,
 built using the HID API library and the Qt GUI toolkit.
 .
 The Funcube Dongle is a small software defined radio receiver for
 64 MHz - 1.7 GHz. It fits into a computer's USB port and uses USB audio
 to transfer complex I/Q data to SDR applications. The control API for
 setting frequency, gain, filter, etc. uses the USB HID standard.
 .
 It provides full support for the Funcube Dongle API::
  * Change frequency and apply frequency correction.
  * Change RF gains and filters.
  * Change IF gains and filters.
  * LNA enhancement, bias current, etc.
  * I/Q correction.
  * Auto-repeat tuning buttons (click and hold button to scan).
  * Variable frequency step.
  * Upgrade and verify the firmware.