frfix: Fieldrunners Sound Fixes (and more!)

frfix overrides a couple functions called by Fieldrunners so that it opens the
correct system audio device and buffers its audio (more) correctly.  As a
bonus, frfix also makes the window resizable, adds a fullscreen mode (press
'f'), and fixes a few potential crashes.

Installation:
 - Untar into your Fieldrunners directory (perhaps /opt/fieldrunners)
 - Run build.sh.  Note that you will probably have to do this as root if
   Fieldrunners is installed system-wide (e.g. in /opt).

Running:
 - use launch.sh to run Fieldrunners