revlog: move censoring code in a dedicated module
This code is quite specific and we are about to add more of it for revlog-v2
(and other derived version). So we move this code in a dedicated module in
`mercurial/revlogutils/`. This looks like a good fit.
The diff is huge because I used `hg copy` to create the new file so that we keep
the history of the censor code.
Differential Revision: https://phab.mercurial-scm.org/D10789
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"conduit_uri": "https://phab.mercurial-scm.org/api",
"phabricator.uri": "https://phab.mercurial-scm.org/",
"repository.callsign": "HG",
"arc.land.onto.default": "@",
"base": "hg:.^"
}