Merge pull request #611 from ammarnajjar/readme-installation

use https instead of ssh with git-clone

README.rst

 ~~~~~~~~~~~~
 
 -  clone source:
-   ``git clone git@github.com:asciimoo/searx.git && cd searx``
+   ``git clone https://github.com/asciimoo/searx.git && cd searx``
 -  install dependencies: ``./manage.sh update_packages``
 -  edit your
    `settings.yml <https://github.com/asciimoo/searx/blob/master/searx/settings.yml>`__