Move the blood and gib type function to monster type class.

Instead of duplicating them in the monster class.

Also refined the test: no default to fd_gibs_flesh but fd_null instead, and check for fd_null when using that function.
Only return specific gib/blood types when the monster is surely made of this.
Also made those function in mtype const.
Prevent chunks of meat from going through walls.

Note that map::bash return true if there was something to be smashed.
This does not indicate that the square is not a obstacle anymore.
New flyer.

Credit to John Candlebury for the idea and the bulk of the text.

Source:
http://smf.cataclysmdda.com/index.php?topic=5847.msg102622#msg102622

Also, I'd never really paid any attention to it before now, but the game
misspells it as 'flier' in the code, but gets it right in-game.
corrects the season offset
Don't create gibs through walls.

Also use break, not a bool variable to break out of a loop.
Words words words.
Ratchet fix
Fix map-extras

Fixes not only tough-to-understand formatting, but roadblocks spawning
away from roads.  Thanks for the tip, vache.
Reduce amount of roadblocks

Folks have been having problems with them in their current (Bugged)
"everywhere" state, so making them omniprersent on roads might not be so
great either.
Chicken walker minimum range decrease

After John Candlebury helpfully informed me that they can be cheesed
with a rifle.  Should make them a little tougher to game, leastwise at
close range.  Extreme long-shots are acceptable.