identify: rename 'changed' keyword -> 'dirty'
I meant to do this before sending the initial templater support, but forgot.
I'm quite surprised that 'dirty' doesn't occur in more user facing contexts, but
there are a few, like the help for blackbox. It also more obviously mirrors the
'(clean)' state printed by the summary command. I also didn't like that it was
just one letter off from {changes} in the {latesttags} sub-keywords, which has a
totally different meaning.
$ rm -rf a
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ hg tag t1 # 1
$ hg tag --remove t1 # 2
$ hg co 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg tag -f -r0 t1
$ hg tags
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24
$ cd ..