refs #30

refs #30

Enable testing on travis-ci.org

refs #30

this builds and runs tests w/o ctest first. Errors here will and should
fail our travis build as such. Afterwards ctest is run again on a
cleaned build dir. This should replicate results and submit those to
cdash, while enabling us not to have the travis build fail due to ctest
itself failing.

refs http://conan2.iwr.uni-heidelberg.de/git/pdelab/dune-
pdelab/issues/58

this way all warnings/errors from building libdunsteuff get included in
the ctest results

i.e. bring back testtools workarounds

it's not whitelisted anyway and we're avoididng surprises this way

try updating pip in a different way