tests/test-symlinks.out

transitive copy/rename

Add support for transitive copy or rename operations, e.g.

    hg rename a b
    ... (possibly edit b)
    hg rename b c
    hg commit ...

by actually renaming "b" as "c" while recording a copy of
"a" to "c" and a removal of "a".

adding foo
adding bomb
adding a.c
adding dir/a.o
adding dir/b.o
! a.c
! dir/a.o
! dir/b.o
? .hgignore
a.c: unsupported file type (type is fifo)
! a.c