Code tweaks.

A follow-up and conclusion to the Lost Nerves event has been added.
A new anomaly can be discovered on a tundra world.
The Frozen Civilization event will now spawn a primitive species on the planet.

Updated Planetary Diversity support.

Adjusted minor artifacts rewards to be on par with the new 3.7 standard.

Updated Russian localisation.

Updated code for 3.7.
Complete rewrite of the core to follow this version's guidelines.
Created a core engine to handle the timed events.
Rewrote all primitive events and added the start of a new event chain.

Added more compatibility to some anomalies.
Added a new anomaly for a Lithoid, Robot or Machine science officer.

Changed the murder events to not remove pops as they no longer represent one person in the game. One pop will be lost if the event is ignored, though.
Added a new anomaly.

Fixed scope error in Crushed event.

Update to the planet types lists for more compatibility.