Preprocessor for BASIC

Most BASICs do not have a preprocessor. ARMbasic does not include one as part of the standard language, but BASICtools uses a modified version of CPP. This adds the functionality of the simple preprocessor that is part of PBASIC, with a number of macros that aid in the translation of PBASIC source to be compatible with ARMbasic.

In addition to CPP, the Unix utility sed is included for additional translation of PBASIC sources.

Both the CPP and sed steps can be included automatically when downloading a PBASIC source with BASICtools.