Added "flags" : ["MODE_BURST"]" to battle rifle conversion mod as one potential solution to issue #6135
Merge remote-tracking branch 'frycarson/BRifleModJSONFix'
Added "flags" : ["MODE_BURST"] to auto-fire mechanism gunmod.
Update mods.json
introduction of armor_layers.h
slow leaks from fuel tanks
corrected for vehicle position and orientation, ensured correct amounts are dropped
add max_volume to furniture and use that instead of MAX_VOLUME_IN_SQUARE
add max_volume to furniture.json, mostly the default 4000, mostly
add NOITEM flag to t_hole
Extend the max_volume setting to terrain
show maximal volume for terrain7furniture and for vehicle parts in advanced inventory
use MAX_VOLUME_IN_SQUARE directly instead of using -1 as placeholder for it
Remove unused definition of MAX_VOLUME_IN_VEHICLE_STORAGE
reserve space for flags description, refresh warmth&enc. block properly
Implemented dirty flag for map transparency cache and outside cache.
Converts most map->grid accesses to wrapper functions.

This'll make it easier to scale this up to 3d, and also to change the way submaps are stored and accessed.

Preliminary work for #6818
Fixed a few bugs with vehicle movement.
astyled code (not sure about spacing in brackets though). added explicit fixes for #7117
add some foldable vehicle parts & make some parts foldable