Use correct order to have container overrides
Add some executable helpers for inspecting state

Those helpers will be used to inspect the container
Make first medium tests passing

* Factorizing most of functionalities into the base medium test frameworks
* Change the large android tests to use abstract commands which enables us to
  hook in and run within the container the same commands
* Use a way to get the tools helper directory within tests
* Move some of the functions into base layer

Note that not all tests are working inside the container yet
Add a way to return immediately to mainloop.

Fix a bug discovered by test when some warnings or errors can happen twice
when we recall ourself with sudo. We need to exit to the mainloop in the
parent process to not redo the same tests.
Knowing that setup can and is inherited, a simple return isn't enough, we raise
then a specific exception that is ignored by the mainloop, then the normal exit
cleanup can happen.
Swith to https and minor cleanup
Workaround an arg not used with bash -c over ssh

Will research for it once online, but even something like:
$ ssh localhost bash -c 'echo baz; echo foo; echo bar' is eating the first
parameter.
Inherit as medium tests android large ones
Larger coverage html regexp for local backups
pep8 fixes
Force google DNS servers

* docker doesn't play with local dnsmasq server, to prevent a warning
  spawing when running tests, use google DNS servers
Disable DNS to not wait on host name resolution

* This was delaying ssh connexion in case of working offline for instance.
Avoid waiting timeout for stopping the container

sshd won't stop. This wins us 10s per tearDown of each tests.
Import whole module instead of parents class

That will avoid we run the parent class tests as discovered by nose.