Updated egenix-mx-base to 3.2.8

egenix-mx-base 3.2.8 was released on 11 Jul 2014. Pip throws an error when trying to install packages with version 3.2.7. Passed all Travis tests.
Merge pull request #3901 from craigappl/fix-egenix-mx-base

Updated egenix-mx-base to 3.2.8