Create order-of-compilation.md

Hi, I am maybefbi from the HypeIRC forums. This is the order of compilation in the CJDNS project.

I created it using a btrace (https://github.com/rprichard/sourceweb/blob/master/btrace/sw-btrace) which loads a shared object into the ./do process which logs to the file when new processes are spawned from it. I parsed the JSON output it generated and looked for spawns of gcc with -c, -S or -E flags.