fairland: Show a more useful map

fairland: Show a more useful map

The map fairland shows has absolute 0,0 in the top-left corner, while
POGO's map * has it in the center.  Shift fairland's map to match
POGO's.

The map shows sea as '.', island sectors as '%', capitals as '#',
mountains as '^', and other continental sectors as a letter or digit
that encodes the continent number modulo 62.  When a continent has no
"other" sectors, its continent number is not shown.  Remove this
pathological case by using letter/digit for capitals, and '#' for
other continental sectors.

Signed-off-by: Markus Armbruster <armbru@pond.sub.org>