Add format & clippy targets to makefile, no longer ignore warnings

1 job for readme-clippy-rustfmt in 1 minute and 37 seconds (queued for 16 minutes and 17 seconds)
latest
Status Name Job ID Coverage
  Test
failed test #199

00:01:37

 
Name Stage Failure
failed
test Test
    = note: #[deny(clippy::needless_return)] implied by #[deny(warnings)]
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_return

error: aborting due to previous error

error: Could not compile `medal`.
warning: build failed, waiting for other jobs to finish...
error: build failed
ERROR: Job failed: exit code 1