created a template for tabgen.c, added error check for command line input
created a makefile for tabgen
tabgen: finished command line argument validation, added resource cleanup
tabgen: added command line argument validation for freq value/breakpoint file
added new_square and new_saw functions to gtable header file
revise new_sine function in gtable library
tabgen: finished soundfile processing (some errors)
tabgen: fixed amp validation error, peak evaluation less stringent
tabgen: added more comments
Merge branch 'tabgen' into develop