Adds Brioche recipe

Brioche is a highly enriched bread with milk and eggs.
Print weapon mods when you activate the weapon.
Fix weapon mod display in the inventory menu.
Remove commented code.
Return hint iffy if are gun doesn't have any mods.
Fix typo.
Coffee shops spawns
doc/contrib/chkjson.cpp: minimalist monkeying of json loading for build checks
doc/contrib/make-chkjson.sh: i hate makefiles
doc/contrib/catajson.h: don't need the function, don't want to bring more code in
doc/contrib/catacharset.h: don't need it sitting there
Allow removing of individual gunmods.
Use the force-- I mean, the make!

Makes `make json-check` a thing, and further teaches the makefile how to
`make chkjson` (or chkjson.exe, on Windows targets). Moves these out
from doc/contrib to src/chkjson, since they are (well) source files.

The new chkjson still depends on its own .cpp, the stub .h,
json.{h,cpp}, and the Makefile, which consists of the minimum
possible attack vector for Jenkins pull request security.
Force item::range() to be a positive number.

I don't know about you, but a negative range just sounds like a bad idea
to me.
Remove catacharset.h dependency from json.cpp.
Merge brioche.

Conflicts:
	data/json/items/comestibles.json
	data/json/recipes/recipes.json
Merge gun mod tweaks.
Merge disallowal of negative values from item::range().
Merge new standalone json checker.