By default, the package was installed in /usr/local/lib/python2.7 in CentOS7.
It is problematic because most of other python packages are installed in /usr/lib
and also because /usr/local/lib is not in the default PYTHONPATH. It's fixed by
overriding the install script and forcing prefix to be /usr.

Added a minimal systemd unitfile.
Adapted tests accordingly.

[ADD] RedHat: defined the dependencies and added a post-install script to create the odoo user, the odoo configuration file, ...

- move packaging stuff to setup
- remove historical stuff
- remove oe, odoo-cmd-fme will be merged with the convered commands
- add an odoo.py script to run odo and boostrap it
- simplify README
- prepare to move documentation to the github wiki