part way through changing player.cpp to add_msg_action
finished modifiying player.cpp
converted melee.cpp over to add_msg_action
fixed ranged.cpp
updated disease.cpp with add_msg stuff
updated iuse.cpp with new add_msg stuff
merged with latest code
merged with latest version; compiles
fixed small bug
Merge player or npc message display.
Refactor handling messages about player or NPCs to be more i18n friendly.
Intelligence dependent skill rust
Added doxygen configuration and doxygen comments to map.h
Doxygen commented mapbuffer.h
Removed cryptic/useless comment that would be recognized as doxygen comment.
Added a doxygen section to CONTRIBUTING.md
Beanbags

Adds beanbag ammos for shotguns and 40mm
Implemented more file checks, standardised error messages
Aligned some code
Added error code exit