Fixed Travis.CI build issues for Clang.
Fixed Travis.CI build issues for Clang.

  Add 'cxxtest' to our test build.
  Updated Travis.CI config to have less cruft.
  Don't need notifications into Gitter (or my inbox).
  Add PPA for CxxTest.

jalcine/wintermute,jalcine/wintermute,jalcine/wintermute