Remove leftover Rust script

For now we removed Rust from the codebase, remove this leftover script.

Also remove some dupes and Rust related files from `.gitignore`.

Author: kassens

compiler/.gitignore

@@ -6,9 +6,6 @@
 debug/
 target/
 
-# These are backup files generated by rustfmt
-**/*.rs.bk
-
 # MSVC Windows builds of rustc generate these, which store debugging information
 *.pdb