Update 0.16

Peasants will now drop a grave when killed. Graves will spawn ghosts over time and require 500 coin to destroy.
Pets will now also drop graves.
Resources will now spawn faster at ore veins.
Added enemy buildings, these buildings will spawn enemies over time.
Made alert sound a bit softer.
Added chance that aggressive animals will have rabies. Villagers can catch rabies off infected animals.
More enemies will be spawned at the start of a new map.
Fixed issue where some wild animals were not being saved.
In the new game screen, when randomizing new maps the colony will not be randomized as well.
In the new game screen added button to randomly generate a new colony.
Added horses to research.
Attacking speed has been decreased, damage will now only be applied every 1 second.