Better shopping cart movenent. It will now be dragged behind the player.

TODO: Check if this works with bigger vehicles as well.
Increase ketchup spoilage time
Lower enc layering penalties
Reduced chewing gum frequency, except on military drops.
Merge some balance tweaks.
Char creation: Profession scrollbar fix.
Add an information message when you start studying a book to tell you how to stop. Addresses #1505.
item: ensure the same default initializers are applied for all constructors as well as item:make. Fixes 'charges' leak in mapbuffer::load
Might as well increment savegame_version since save compatibility was busted
since the 1st. Also, made a global variable
Merge fix to character creation scrollbars, reading cancallation notification, and item initialization unification.

Conflicts:
	game.h
	item.h
Merge remote-tracking branch 'dda/pr/2840' into dda-master
Fix vehicles not having foot pedals.
Merge pull request #2885 from ianestrachan/fix-2880

Fix vehicles not having foot pedals.