Change git URL and cloning text/repository name after project rename

As someone highlighted it on the IRC channel, repository and issue URLs were not updated after past repository and group renaming, as it resulted in broken URLs (404, it doesn't seem like Gitlab handle any form of redirect)

This commit change part of the doc as well to reflect the change.

However, grep did match other parts:

clement@mbp:~/repositories/memopol$ grep -irnI political_memory . ./.travis.yml:36: repo: political-memory/political_memory ./docs/deploy-openshift.rst:15: Cloning into 'political_memory'... ./docs/deploy-openshift.rst:23: $ cd political_memory/ ./docs/development.rst:23: $ cd political_memory ./docs/development.rst:59: Cloning into 'political_memory'... ./docs/development.rst:67: $ cd political_memory/ ./docs/development.rst:81: Obtaining file:///tmp/political_memory ./docs/hacker.rst:19: $ cd political_memory/ ./setup.py:12: url='http://github.com/political-memory/political_memory/', ./src/memopol/templates/home.html:129: <a class="btn btn-default" target="_blank" href="https://git.laquadrature.net/political-memory/political_memory"> ./src/memopol/templates/home.html:133: <a class="btn btn-default" target="_blank" href="https://git.laquadrature.net/political-memory/political_memory/issues/new">

Should Travis stay there if nothing remains on Github?

I didn't touched matches for the pip package. Should it be updated as well? (development.rst:81 and setup.py). Is the pip package to be renamed too?