plainbox: mock-away requirements for readthedocs.org

This patch removes the need to install plainbox dependencies for setup.py
when invoked by readthedocs.org. All the externally imported modules are
mocked in conf.py, by injecting a Mock() object into sys.modules.

This operation has no negative effects for the documentation as we are
not relying on any real properties of those dependencies. It also makes
the process much faster and more robust, especially since lxml cannot
be installed from pypi without additional system-level dependencies.

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
plainbox:setup: make setup work when invoked from other directory

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
checkbox-ng: mock-away requirements for readthedocs.org

This patch removes the need to install checkbox-ng dependencies for
setup.py when invoked by readthedocs.org. All the externally imported
modules are mocked in conf.py, by injecting a Mock() object into
sys.modules.

This operation has no negative effects for the documentation as we are
not relying on any real properties of those dependencies.

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
checkbox-ng:setup: make setup work when invoked from other directory

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
setup.py: add top-level multiplexing setup.py

This special setup.py file is designed to work with readthedocs.org that
currently has no support for selecting one of many available setup.py
files (like it does have for conf.py files).

The new setup.py file, when invoked, dispatches the command to selected
setup.py files (currently plainbox and checkbox-ng). This works well for
the action that readthedocs.org requires, which is `setup.py install
--force`.

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
tarmac-verify: trigger rtfd.org rebuild after testing

This acts as a poor-man's post-land hook that we invoke from our tarmac
build / test machine. It causes a rebuild to be triggered on rtfd.org

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>