FloorContext defines a range between floors, and includes enough information
to tell if a car is in that range, and what the stop at the end of the range
and the next stop after that range would be.
verifyRotation
returns the best rotation for the string (ROTATE_NONE, ROTATE_LEFT, ROTATE_RIGHT)
This is public static so you can use it to test a string without creating a VTextIcon
from http://www.unicode.org/unicode/reports/tr9/tr9-3.html
When setting text using the Arabic script in vertical lines,
it is more common to employ a horizontal baseline that
is rotated by 90¡ counterclockwise so that the characters
are ordered from top to bottom.