[merge] from 0.3.2
[evol] quick code to handle running an external script to reload the zone (needed for signed zones)
[evol] added session management to the cyborg server (refs #31)
[fix] DNS service fixes
[fix] typo
[fix] DNS fixes
[evol] reworked DNS classes (refs #31)
[evol] work on cyborg server protocol and API #7 (refs #31)
[evol] uncomplete MapMaker bot implementation (global cyborg classes, use of EventMachine with UNIX socket backend, configuration adjustments, ...) (refs #31)
[licence] updated copyright years and added missing headers
[evol] add missing licensing terms
[evol] backup zone before replacing, reload zone, and rollback zone if reload failed
[evol] implement changing a zone
[evol] new DNS class to manage zone files (only read zone file at the moment) + generate proper mail reply