Moved 12 functions from sequencetools to mathtools.

OLD:

    sequencetools.all_are_equal
    sequencetools.all_are_integer_equivalent_exprs
    sequencetools.all_are_integer_equivalent_numbers
    sequencetools.all_are_nonnegative_integer_equivalent_numbers
    sequencetools.all_are_nonnegative_integer_powers_of_two
    sequencetools.all_are_nonnegative_integers
    sequencetools.all_are_numbers
    sequencetools.all_are_pairs
    sequencetools.all_are_pairs_of_types
    sequencetools.all_are_positive_integer_equivalent_numbers
    sequencetools.all_are_positive_integers
    sequencetools.all_are_unequal

NEW:

    mathtools.all_are_equal
    mathtools.all_are_integer_equivalent_exprs
    mathtools.all_are_integer_equivalent_numbers
    mathtools.all_are_nonnegative_integer_equivalent_numbers
    mathtools.all_are_nonnegative_integer_powers_of_two
    mathtools.all_are_nonnegative_integers
    mathtools.all_are_numbers
    mathtools.all_are_pairs
    mathtools.all_are_pairs_of_types
    mathtools.all_are_positive_integer_equivalent_numbers
    mathtools.all_are_positive_integers
    mathtools.all_are_unequal

CHANGE: should be noted in the 2.15 change log.