added GTABLE definition, new_sine function, and gtable_free function to the gtable library
created a makefile for the gtable library
added OSCILT type definition, oscilt_tickfunc, and new_oscilt, tabtick, and tabitick functions to the gtable library
added new_triangle function to the gtable library
added new_gtable and norm_gtable functions to the gtable library
gtable: turned norm_gtable into a static function
gtable: revised new_triangle function
added new_square and new_saw function to the gtable library
Merge branch 'gtable' into develop