Add the ability to mod mouse cursors

This supports cursors for:
* Hovering over map events and loot
* Hovering over living enemies
* Hovering over NPCs

As well as a normal cursor.
Allow setting offsets for modded mouse cursors
Fix cond jump on uninitialized var.
Dont recreate title LabelWidget on each render.
Dont recreate label on each render.
Prevent creating label on each render in WidgetSlot
Dont create new WidgetLabels on each render()
Run indentation script.
Don't create a WidgetLabel on each call to render()
Remove init of shared icons resources from RenderDevice.
Added a SharedResources class with static init functions.
This is a part of issue #969
Reload icons after recreating render context
Merge pull request #979 from dorkster/fixes

Reload icons after recreating render context
Merge pull request #977 from dorkster/mouse_cursor

Context sensitive mouse cursor graphics
Reinitialize CursorManager when changing mods or resolution
Merge pull request #980 from dorkster/fixes

Reinitialize CursorManager when changing mods or resolution
Merge remote-tracking branch 'upstream/master'

Conflicts:
	src/SharedResources.cpp