Support new 1.17+ Forge JPMS arguments that don't ship any executable jar. It will use unix_args.txt file for 1.17+ when one exists, otherwise defaults to using the jar file
Fix forge latest build version option to actually use latest instead of recommended
Set build version input rules to only accept valid values of the latest and recommended
Remove spaces from the version variables to avoid issues with curl. Forge site displays versions with spaces to end users
