Added "minimal" test case for costFunctionReg

- These tests use only 0s and 1s for the matrices, mainly, and allow you
  to find if you've got the very basics of the algorithm working. For a
  more detailed test of costFunctionReg see test_costFunctionReg.m from
  community TA Collin Beckingham which uses magic(3) and non-trival values
  for theta and y