doc: update copyright years to 2012
I sometimes look at a piece of software and if the man page says
"Copyright 2004", then I'm inclined to think that the project is stale
or that the authors are lazy. Neither is good publicity for us :-)
$ hg init dir
$ cd dir
$ echo bleh > bar
$ hg add bar
$ hg ci -m 'add bar'
$ hg cp bar foo
$ echo >> bar
$ hg ci -m 'cp bar foo; change bar'
$ hg debugrename foo
foo renamed from bar:26d3ca0dfd18e44d796b564e38dd173c9668d3a9
$ hg debugindex bar
rev offset length base linkrev nodeid p1 p2
0 0 6 0 0 26d3ca0dfd18 000000000000 000000000000
1 6 7 1 1 d267bddd54f7 26d3ca0dfd18 000000000000