tests/test-empty-dir.t

profiling: replace '+' markup of nested lines with indentation

The display of nested lines for hg --profile was very non-obvious and made it
look like sort didn't work.

The '+' immediately before CallCount was not related to the CallCount and did
not mean plus in any integer sense.

The '+' before module looked like a part of the module name and not like ascii
art.

Instead we now indent the subordinate module names to clearly show the
structure.

  $ 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