rewrite OpenStoreRentWindow so as not to require UpdateVarAssoc
clean up handling of bad/invalid item properties by forcing sensible defaults
don't leak the item info
improve error reporting when a bag is full
don't reactivate spawn points with living spawns in the area
don't place persistent actors again for already loaded areas

Fixes CheckForReplacementActor spawning multiple copies of replaced
actors on area transition. Also truly delete replaced actors, and
fix an off-by-one error in the replacement loop.
fix leak when buying items from a store
some general changes in preparation for IE_ANI_NINE_FRAMES update
allow multiple palettes for dragon animations
fix dragon attack animation
SendTriggerToAll: also send to area itself

Fixes Vithal not appearing in AR2100 when Freedom spell is cast
(BG2).
yet more robustness when faced with broken dialog scripts

Also handle the mergestrings case properly when an argument is not
terminated with quotes. Fixes udvith.dlg in BG2.
add new flag to check for unscheduled actors in ValidTarget

It turns out unscheduled actors can be targeted after all, e.g. for
the Activate() script action.
SDL2: fix save screenshots being black.
TouchInput: fix rightclick not ignoring next finger up
touchInput: fix repeat mouse events causing stuck buttons
touchInput: remove ignoreNextFinger decrement from ClearFirstTouch
TouchInput: only right click if we arent already ignoring finger ups

if we are in a gesture for example we dont want to inadvertently issue a right click
TouchInput: fix viewport scrolling when a button has focus

we may need to add other (unscrollable) control types too.
touchInput: only begin a drag gesture if the movement delta is <= the min