ClutTeX version 0.6

Changes:

• Fix "arg" table in luatexinit to support luamplib
• Handle the combination of --output-directory and --change-directory properly (Issue #7, thanks to @atticus-sullivan)
• Change LUAINPUTS environment variable to find Lua files if --change-directory is used (PR #11, thanks to @atticus-sullivan)
• Watch engine can be selected via an optional argument to --watch (PR #10, thanks to @atticus-sullivan)
• Decrease max_print_line to avoid issue with BibTeX from TeX Live 2023.
• Rerun biber if bib files are updated (PR #12, thanks to @atticus-sullivan)