Saves preprocessor output and generated assembly to separate files.

* preprocessor:
  * https://stackoverflow.com/questions/3742822/preprocessor-output/76127046#76127046
  * https://stackoverflow.com/questions/985403/seeing-expanded-c-macros/60816758#60816758
  * https://stackoverflow.com/questions/4900870/can-gcc-output-c-code-after-preprocessing/55477371#55477371
* assembly:
  * https://stackoverflow.com/questions/137038/how-do-you-get-assembler-output-from-c-c-source-in-gcc/56801917#56801917


 Discussion on "gcc -save-temps" by Ciro Santilli (@cirosantilli, 34)

 Discussion on "gcc `-save-temps`" by Ciro Santilli (@cirosantilli, 34)