[bounty] Does not build on Ubuntu 13.10

The purpous of this bug report is to set up a bounty to re-ignite the GTK front-end development.

Bounty: https://www.bountysource.com/issues/1360904-bounty-does-not-build-on-ubuntu-13-10

The lp:bzr-gtk (Gtk+3 gui) does not build Ubuntu 13.10.

The error when trying to build:
$ ./setup.py build
running build
running build_py
running build_scripts
running build_credits
Traceback (most recent call last):
  File "./setup.py", line 209, in <module>
    'check': Check}
  File "/usr/lib/python2.7/distutils/core.py", line 152, in setup
  File "/usr/lib/python2.7/distutils/dist.py", line 953, in run_commands
  File "/usr/lib/python2.7/distutils/dist.py", line 972, in run_command
  File "/usr/lib/python2.7/distutils/command/build.py", line 128, in run
  File "/usr/lib/python2.7/distutils/cmd.py", line 326, in run_command
  File "/usr/lib/python2.7/distutils/dist.py", line 972, in run_command
  File "./setup.py", line 84, in run
    from bzrlib.plugins.stats.cmds import find_credits
ImportError: No module named stats.cmds

Goal: Make bzr-gtk (gtk+3) build and run (all gui aspects) on the current* (and latest LTS) version of Ubuntu and Debian**.

* Current: the version latest stable version.
** I will probably not test if it runs on Debian.