Lower mole size to TINY
Move digging checks to a separate function
Removed moles, changed some monster symbols.
Update monster::move_to() style
Add dirt mound formation size chance
Move sludgetrail effects, remove unneeded hallucination checks
Factor for vermin in dirt mound formation chance
Mole/shrew tweaks

Made vermin, small hp tweaks
Merge to mainline

Conflicts:
	data/json/monsters.json
Merge mole removal as well as fix to vermin burrowing.

Conflicts:
	data/json/monstergroups.json
	data/json/monsters.json