DWITE 2007-10: Added problems, solutions, and tests.
DWITE 2007-11: Added problems, solutions, and tests.
DWITE 2011-10 P3: Added hashCode() to Vector because equals() is overridden, to fix compiler warning.
DWITE 2007-10, 2007-11: Made minor edits to problem statements - mainly for wording, grammar, punctuation.
DwiteAlgorithm: Simplified newIntGrid() and made 2 solutions use it.