Gitarootools

- (gm-pakunpack) fix gm-pakunpack not working

- (gm-gmo2animnames) add tool gmo2animnames to extract animation names from GMO models
- (gm-pakpack/pakunpack) add tools gm-pakpack/pakunpack for Gitaroo Man Lives! PAK files
- Support for Python 3.10 and 3.11

- (gm-png2imx) regarding color quantization (converting to a 256- or 16-color image) and
[Pillow issue 5204](https://github.com/python-pillow/Pillow/issues/5204) (where
quantization reduces colors too much in some cases, usually affecting images that have
transparency):
- A warning will be printed if an image is negatively impacted by Pillow issue 5204.
- An input image that already has few enough colors (256/16 or fewer) will no longer
be impacted by Pillow issue 5204.
- drop support for Python 3.6

- now works with Python 3.9

- (gm-imx2png/png2imx) add tools gm-imx2png/png2imx

- (gm-xgmpack/unpack) add tools gm-xgmpack/unpack
- (all IMC/subsong tools) simplify help text
- (gm-imcunpack) change names of created directories (e.g. TITLE_IMC instead of TITLE)