rewrite of overmap::find_closest.

this thing was an npc stumbling block because
it didn't scan everything and was so slow.
Added NPC nullification files, and icon files
Changed mode I think.
Saved modified cbp
And again, removed -x flags
Switch uint32_t and int32_t to int to match rest of code and un-break code that allows signed skill levels.
Replace bandages or first-aid in inventory if application is cancelled.
Boundary checking for bridges crossing overmap borders
Durr, even more overmap vs. river vs. bridge boundary checking

Dunno if bridges between overmaps should even be legal.
Initialize webs properly in mapgen. Avoids weird bug where fields stop updating if you burn the webs.
Merge branch 'master' of github.com:TheDarklingWolf/Cataclysm-DDA into for-darklingwolf
Moved drugs that were in misc to chem section
Merge branch 'master' of https://github.com/TheDarklingWolf/Cataclysm-DDA
Add bindist files to the .gitignore
Add launcher for Linux/OS X users to double click
Merge pull request #41 from hovatterz/gitignore

Add bindist files to the .gitignore
Merge pull request #42 from hovatterz/launcher

Add launcher for Linux/OS X users to double click