Use arrows from bmp for e/w to have same style as n/s

[lucianposton]

In unicode map drawing mode, the north/south arrows were from the basic plane, while the east/west were from the supplemental plane.

This changes the east/west to basic plane. This makes the arrows have a consistent style, as well as will be better supported, since many fonts don't have glyphs for supplemental planes.

Existing maps won't be affected since the default hardcoded values are copied into the map file when written.

[lucianposton]

Now the n/s and e/w arrows are consistent. :)

[scandum]

Some issues where reported with those arrows on other systems, but I've added it as a comment upstream.