Mods can now have their own lua files.

Furthermore, added game.dofile function, which executes a lua file from the current mod directory.
Fixed unused parameter warnings.
fix turret activation use of wrong ammo
Replace ascii-math based construction menu hotkeys with an explicit list.
Only highlight constructions when the player can build them.
Random line wrap fix.
Move construction internals into .cpp file.
ignore the pointer to the menu window when it's NULL
make choose_escape_item and use_escape_item use the item position system, not invlets

both player::use and player::consume use the item position as parameter
Make npc::use_painkiller consume the item by its position (what player:consume expects)
readded onhit effects
more onhit changes
Fixes overly-long query in cannibalism scenario.

There's not really any reason to use the extra space when we already
have a shorter phrasing in other, similar cases.
astyle
fix item description
Renamed migo_speech to speech.json
fixed documentation
Merge pull request #6264 from Rivet-the-Zombie/cannibal-message-fix

Fixes overly-long query in cannibalism scenario.
Merge pull request #6269 from Soyweiser/Migo_speech_rename

Migo speech rename
Move '$' symbol to beggining of the price