State machines for services

We need to design some FSM for the services like EIP and email.

We may want to consider these options: https://github.com/glyph/automat/ https://machinist.readthedocs.org/en/latest/ http://xworkflows.readthedocs.org/en/latest/reference.html https://github.com/rbarrois/xworkflows

I've made some tests with xworkflows in the past -> https://gist.github.com/ivanalejandro0/2607235403cb22bd3620

Different services need to be started under certain conditions, for instance, (in some cases) we need to wait until Soledad is started to launch mail, or that EIP is started to do login.

(from redmine: created on 2015-10-05, relates #5616 (closed), relates #7882 (closed))