Get rid of the dedicated Emoji class to make it easier to store a null
value signifying a failed lookup.
This allows us to remember failed lookups, making subsequent failures
for the same codepoint much faster. :^)
Instead of LibGUI and WindowServer building their own copies of the drawing
and graphics code, let's it in a separate LibDraw library.
This avoids building the code twice, and will encourage better separation
of concerns. :^)
