Merge in numerous local fixes: - when outputing character to the screen check
that we actually have a character for the charcode supplied. This fixes
potential segfault when user types in some character that isn't in the
table; - don't hog all CPU time when playing level completion sound. This also
makes level completion sound much more less jerky; - by default use sdl12
library instead of sdl10, because sdl10 is at the end of its lifecycle and
would be retired RSN.
Add several patches for the sdl version of digger. These patches fix the game
when used with SDL-1.2.x and also add some new functionality (ability to
switch to/from fullscreem mode). Since files being patched aren't used right
now the PORTREVISION remains the same.