Change of functions order in drive.h to facilitate Valentin's work merge.

[riccardosavorgnan]

What did I do?
I took the existing drive.h files and I re-ordered all existing functions to match the order they’re in in Valentin’s branch, following these rules:

• if a function is not in Valentin’s file we move it at the end of the file;
• if a function is not in the original drive.h I place a // void function_name(void){} comment as a placeholder;
• if a function has been clearly renamed to something else I added a comment on top: // rename to: new_function_name
• I moved render functions in their section at the end, Valentin moved them in a new file render.h, but we’ll do that later.

Why?
This way we’re keeping a working file (this is just COPY PASTE WORK), and the work by Valentin can now be introduced progressively without freaking out the diff.