Naturalist profession

Absolutely no industrially-manufactured equipment, but highly talented
and immediately (and extensively) survivable. 6 points feels like an
appropriately hefty cost. Definitely not geared for subprime warfare,
though, with only 20 good arrows. Feels balanced to me.

Also adds a new "Wilderness" scenario that the Naturalist is limited to.
Nothing more or less than "you're in the woods". Wouldn't make
roleplaying sense for them to flee to shelters. Added compatibility for
other outdoorsperson types for the heck of it.
Ideally this would be in Construction (`"carpentry"` in the code) for stone axes and shovels.  But then the character could be Not Into that sort of extreme terrain modification.  I'll leave it as is, and we can revisit later if need be.