util: implement a deterministic __repr__ on sortdict
`hg debugbundle` is calling repr() on bundle2 part params, which are
now util.sortdict instances. Unfortunately, repr() doesn't appear
to be deterministic for util.sortdict. So, we implement one.
We include the type name because that's the common convention for
__repr__ implementations. Having the type name in `hg debugbundle`
is a bit ugly. But it's a debug command and I don't care enough to
fix it.
$ hg init
$ echo This is file a1 > a
$ hg add a
$ hg commit -m "commit #0"
$ ls
a
$ echo This is file b1 > b
$ hg add b
$ hg commit -m "commit #1"
$ hg co 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
B should disappear
$ ls
a