upgrade: add '-' in optimization name
The older name `redeltaall` was hard to type and read. The newer form should
be more user-friendly.
We keep backward compatibility with the old form (at least for a while).
Having to use different form depending on the version is very impractical and
error prone.
https://bz.mercurial-scm.org/1089
$ hg init
$ mkdir a
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b
$ hg ci -m m a
$ mkdir a b
$ echo a > a/b
$ hg ci -Am m
adding a/b
$ hg rm a
removing a/b
$ cd b
Relative delete:
$ hg ci -m m ../a
$ cd ..