Marcus Nordstedt

Added the tests to a few methods to increase branch coverage. In the process we discovered a bug which is described in issue #165. #### By submitting this pull request...

We added the following test (in MathematicsTests) which checks that the method Multiplication.multiplyUsingLoopWithStringInput works correctly when multiplying with zero. It fails with the error below Test: @Test public void testMultiplyUsingLoopsWithStringInputZero(){...