global: travis fixes

* Adds the language key (otherwise, it's ruby).

* Enables the Python 2.6 build.

* Downloads the devscripts where they want to be downloaded.

* Adds fixes because kickstart is run from a venv.

* Uses some corrected devscripts (FIXME to be removed).

Signed-off-by: Yoan Blanc <yoan.blanc@cern.ch>