Tag info saved in model metadata ignores keep_tokens_separator

Tag info saved in model metadata ignores keep_tokens_separator.

For example with keep_tokens_separator = ## and caption 1boy##standing, red the metadata will save tags 1boy##standing, red while training will use 1boy, standing, red.
Metadata should also save 1boy, standing, red in tag frequency.

Probably other caption modifiers are also broken.