move file_exist to file_wrapper.h/cpp
Fixes description for bio_face_mask.

The unit itself got the right description, but the packaged model
didn't.
Also blade.
Fixed placeholder description.
Merge branch 'master' of https://github.com/CleverRaven/Cataclysm-DDA into CBM-description-fix
check for io-errors when saving a character template
add checks for io-errors in various save-functions
add message if writing default mods fails
add map::sees_some_items to check if player can see any items somewhere

use function in cata_tiles and in game.cpp
Spray canning or magic markering now takes time. Using a magic marker on an item takes 10 turns. Writing on the floor message length * 2 time.
Changed item description of notes from:
"%1$s on this %2$s is a note saying: "
into:
"%1$s on the %2$s is: "

So you get "Carved on the cooked meat is: I USED TO BE A CAT"
And not "Carved on this cooked meat is the note saying: I USED TO BE A CAT" which was a bit odd.

Removed the time usage from writing on objects. As you can also leave notes on objects in other ways I and I not know them all. So all or nothing. For now, only writing on floors takes time.
Put the (void)p; //unused back in.
Merge pull request #6074 from BevapDin/fields

Fix for #4260
XL survivor armor!
make most save methods return false if they failed to save

moved save_maps, save_artifacts, save_factions_missions_npcs to game::save

don't quit after failed saving
Tweak.
Materials fix.
Additional futuristic materials.
Merge branch 'impreove-writing-files' of https://github.com/BevapDin/Cataclysm-DDA into BevapDin-impreove-writing-files
Merge branch 'CBM-description-fix' of https://github.com/Rivet-the-Zombie/Cataclysm-DDA into Rivet-the-Zombie-CBM-description-fix