Travis doesn't support cmake version higher than 2.8.9.
Merge pull request #17 from ahmedcharles/travis_cmake

Travis doesn't support cmake version higher than 2.8.9.

We still backport to 2.8.11 but this will make it so those on lower Cmake versions can build error free.
Deleting the host will make pH a dangling pointer, so remove it from mTabMap first.