[Tutorial] How to Sync & Compile Luma3DS

There were some users that wanted to compile Luma3DS themselves but run into problems. There is already a guide that explains how to sync and compile rxTools, so most of the stuff here is stolen from this guide: https://gbatemp.net/threads/noob-proof-guide-to-compile-rxtools-source.392242/ (thanks btw @capito27. Your guide helped me compile rxTools back then and made me understand some of this shi-- stuff. ).

I try to keep the guide simple is both...

[Tutorial] How to Sync & Compile Luma3DS