[PATCH 0/2] Controversial blob munging series

This is on top of 'next' I'll push out after I am done with v1.5.1.2 I am preparing today.

[1/2] Add 'filter' attribute and external filter driver definition. [2/2] Add 'ident' conversion.

I'll park them near the tip of 'pu', but consider they are primarily for interested people to experiment with.

I suspect this might have helped me (and other Asians) a year ago. I did not manage to configure my Emacs to work well with utf-8 encoded Japanese text, and had some difficulties in maintaining documentation for git-lost-found (it has my name spelled in Japanese).

I could have had:

	(in .git/info/attributes)
	Documentation/git-lost-found.txt filter=eucjp-n-utf8

	(in config)
	[filter "eucjp-n-utf8"]
		clean  = nkf -E -w
		smudge = nkf -W -e

so that checked-out copy is after "nkf -W -e" (filter to EUC-JP, treating the input as UTF-8) to allow my Emacs work with EUC-JP. Check-in will be done after "nkf -E -w" (filter to UTF-8, treating the input as EUC-JP), which would keep the "official" version in the repository as UTF-8. The best part of this is that the configurations above are both private to me, and people do not even have to know that I am suffering from the inability to use UTF-8 in my editor.

These days I configured my Emacs to deal with UTF-8 much better than when I added git-lost-found manual page, so I would not need the above hack, though.

I also suspect a "fun but probably not very useful in practice" application would be to have "indent" as the clean filter while leaving "smudge" filter empty.