tests/test-addremove.out

extensions: load and configure extensions in well-defined phases

Extensions are now loaded with a call-graph like this:

  dispatch._dispatch
      extensions.loadall
          extensions.load
                # add foo module to extensions._extensions
          extensions.load
                # add bar module to extensions._extensions

          foo.uisetup(ui)
          bar.uisetup(ui)

      foo.extsetup()
      bar.extsetup()

      commands.table.update(foo.cmdtable)
      commands.table.update(bar.cmdtable)

  hg.repository
      foo.reposetup(ui, repo)
      bar.reposetup(ui, repo)

The uisetup calls could easily be moved out to dispatch._dispatch, but
have been kept in extensions.loadall since at least TortoiseHg calls
extensions.loadall and expects it to call uisetup.

The extensions.load function called uisetup. It now has an unused ui
argument which has been kept for backwards compatibility.

adding dir/bar
adding foo
dir/bar
foo
committed changeset 0:d44511117907
adding dir/bar_2
adding foo_2
dir/bar_2
foo_2
committed changeset 1:a85812e0561a
adding a
adding c
removing a
adding b
removing c
adding d
recording removal of a as rename to b (100% similar)
removing a
adding b
removing c
adding d
recording removal of a as rename to b (100% similar)