Raspbian backend for OpenWISP 2

The project will require to implement a backend for OpenWISP 2. The backend must generate Raspbian compatible configuration files (i.e. etc/resolv.conf, etc/network/interfaces, etc/hostapd/hostapd.conf, etc ) from NetJSON Device Configuration. The backend must also be capable of generating NetJSON Device Configuration from the Raspbian configuration files. The backend must atleast conver General, NTP Settings, Wireless Settings, Wireless Settings, DNS Server, DNS Search Domains, Static Routes, Files, etc. The test coverage of the library must be above 95%. The backend will be documented inside python-sphinx docs directory contained in the netjsonconfig repository.