Removed qtsixa and utils directories

Preparing for a standalone sixad application (command line only)
Added sixpair for setting bluetooth master address
Renamed 'sixad' to 'sixplay'
Changed 'cout' to 'printf'
Changed 'cerr' to 'fprintf(stderr, ...)'
Changed all relevant includes to c-style
Added sixpair to the install script
Removed c++ style memory allocation

Part of changing code to ANSI C
Fixed all gcc compile errors

Renamed all source files from .cpp => .c and fixed any subsequent compile errors