GRAPHICS: Compensated negative xMin in TTF characters differently

We really want the width of the character to stay the same, so
instead of adjusting the width, we just don't draw the part that's
outside of the left boundary.
COMMON: Add UString constructor that adds n copies of a codepoint
COMMON: Document the different UString constructors
ENGINES: Add a progress bar visualizing game loading

This way, everything should be clear and obvious even
when not looking into the console output.
NWN: Show loading progress with LoadProgress
KOTOR: Show loading progress with LoadProgress
KOTOR2: Show loading progress with LoadProgress
NWN2: Show loading progress with LoadProgress
JADE: Show loading progress with LoadProgress
SONIC: Show loading progress with LoadProgress
WITCHER: Show loading progress with LoadProgress
DRAGONAGE: Show loading progress with LoadProgress
DRAGONAGE2: Show loading progress with LoadProgress