added: test for predictOneVsAll
commented out: unstable oneVsAll test; non-standard predict tests
Merge branch 'ex4'
Merge branch 'ex5'
added: unit tests for ex6
added: ex7 unit tests
added: another test for computeCentroids
Merge branch 'master' of https://github.com/vasnake/coursera-ml005-unittests
computeCentroids: Test for pen-and-paper calc.

Added another test for Ex7 Test 2 "Compute Centroid Means". A simple
test that can be calculated by hand to check that the code is working.