Move `lib/support.rs` to zinc crate

Putting this functions into the top-level file seems rather natural, as they are hierarchically a level higher  then this, and for the lack of better name it seems rather okay to have them in `main.rs`.  As discussed in #106, this remove a bunch of functions that are no longer needed and only keeps the ones it doesn't compile with. It's been verified that there no symbols pulled into the ELFs from anywhere that would be the same as the ones removed by this change.

I have tried to rename `main.rs` to `lib.rs`, as it appears to be the current convention, but it screwed the hell out of rake and it blew up with "stack level too deep" exception, which I found quite funny...
That's what I was thinking at the start! Thanks, will move it back :+1: