Changed crafting difficulty of some arrows

Changed Fabrication difficulty of Sharpened Metal Arrows, Heavy Fletched
Field Point Arrows, and Heavy Fletched Fire-Hardened Arrows from 5 to 4.

Previously, all components for heavy arrows were level 3, while all
heavy and metal arrows were level five, creating a gap in leveling
progress.   This update allows the improvised point heavy arrows to
serve as fabrication skill stepping stone.  Now archers don't have to
spend level 4 pointlessly grinding through unrelated recipes, but the
vastly superior Heavy Wooden and Metal arrows are still sought after.
actually fix the motel.
.
Alters 'grill' encumbrance.

They really shouldn't make it that hard to breathe on their own.
CanvasSacksVolume

As with the rest of non rigid containers, there is no reason for them to
have such high volume if empty. If full, total volume is calculated as
volume of container + volume of content.
Graffiti on the ground should be written to log when you enter the tile

This commit fixes bug #9220 and #9300, where graffiti text was only written to log when you left the tile it was written on.
Merge pull request #9369 from tivec:

- read graffiti on the ground when walking *into* the tile, not when
walking *out* of it.
Merge pull request #9367 from Rivet-The-Zombie:

- stop dental grills from encumbering you quite so much.
Ignore chkjson.d along with chkjson, the binary.

- Just a trivial gitignore update, no pull request.
Merge pull request #9364 from Skidborg/arrow-crafting-progression

Fletching Difficulty Tweak
Merge pull request #9368 from Robik81/CanvasSacks

Canvas Sacks Volume
Changes required skill for survival shelter to survival.
Merge branch 'shelter-skill' of https://github.com/Rivet-the-Zombie/Cataclysm-DDA into merge2
Merge branch 'confusing-mapgen' of https://github.com/Lain-/Cataclysm-DDA into merge2