status: add the --change option to display files changed in a revision
This option is similar to the one already used for the diff command.
Unfortunately, the c and C short option are already used for status, so there
is no corresponding short option. However, there is no short option for --rev
either, so that's consistent.
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
removing b
created new head
% should abort
abort: crosses branches (use 'hg merge' to merge or use 'hg update -C' to discard changes)
% should succeed
1 files updated, 0 files merged, 0 files removed, 0 files unresolved