graft: store user passed date and user information in graftstate
Right now, `hg help graft` says:
The -c/--continue option does not reapply earlier options, except for --force.
which should be treated as a bug.
A good user experience is that the commands remember the arguments passed
initially and preserve them during `hg graft --continue`.
This patch starts storing the user and date information in graftstate if user
passed it. Upcoming patches will make sure we preserve that information during
--continue and them don't allow user to pass any new arguments with --continue.
I don't think there is any another `--continue` flag which allows new options to
be passed with it.
Differential Revision: https://phab.mercurial-scm.org/D3657
$ hg init
$ echo 123 > a
$ hg add a
$ hg commit -m "first" a
$ mkdir sub
$ echo 321 > sub/b
$ hg add sub/b
$ hg commit -m "second" sub/b
$ cat sub/b
321
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ cat sub/b 2>/dev/null || echo "sub/b not present"
sub/b not present
$ test -d sub || echo "sub not present"
sub not present