Scheduler rename

• Adds strings to scheduling language (though with a very limited character set, there are no special symbols except _, -, and spaces; basically this is intended as strings that are reasonable for function names and file names).
• Adds a rename pass which allows us to rename functions to avoid having to access pass results using generated function names.

requested review from @rarbore2

assigned to @aaronjc4

enabled an automatic merge when all merge checks for 06f747ca pass

mentioned in commit d19be298

merged