FIX: a shot at fixing the "_" underscore problem in fileutils.c. This one uses _ifde...

FIX:  a shot at fixing the "_" underscore problem in fileutils.c. This one uses _ifdefine. I hope it works. Linux people can let me know if it works.

FIX: changed the DetectASKClock in lfdemod.c to correct detect all clocks in the array.
CHG: I like code with more spaces inside of it and tried change some stuff according to our codestyle in HACKING.txt
ADD: some zero checks and overflows, god knows where it was.

The T55XX commands will be rewritten to use Marshmellows lfdemod.c instead.
CHG: Made the graph window smaller.
CHG: lf read  now does a "data samples" also.  (less writing commands)
CHG: data samples now defaults to samples size of 20000