largefiles: test reverting largefiles (coverage creeping ever upwards)
This reveals a small bug: revert reports "reverting .hglf/largefile"
when it really should report "reverting largefile". I don't see an
easy fix, though (short of using ui.pushbuffer() to interfere with
revert's output).
$ 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