Thun/implementations/C

Thun in C

This is my first attempt to write C in many years, I hope it's not too embarassing.

I use Gperf to create a static wordlist. This make word lookup very efficient, but there's no way currently to add definitions at runtime.

There's a janky script convert_defs.py that generates definitions.c, definitions.h, and KEYWORDS.txt from the defs.txt file. I would like to replace the dependency on Python with, say, Awk or something.