Restrict PE testing to Python 3.7 on Linux

.travis.yml

@@ -76,7 +76,8 @@ install:
 
   # If were using python 3.6 or higher and we're decrypting an OE key, install OFF toolkit and
   # OETK (there aren't OFFTK packages for python<3.6)
-  - if [ ${PYTHON_VER} != "2.7" ] && [ ${PYTHON_VER} != "3.5" ] && [ "$TRAVIS_SECURE_ENV_VARS" == true ] ; then conda install --yes -c omnia -c openeye openforcefield openeye-toolkits propertyestimator; fi
+  - if [ ${PYTHON_VER} != "2.7" ] && [ ${PYTHON_VER} != "3.5" ] && [ "$TRAVIS_SECURE_ENV_VARS" == true ] ; then conda install --yes -c omnia -c openeye openforcefield openeye-toolkits; fi
+  - if [ ${PYTHON_VER} != "2.7" ] && [ ${PYTHON_VER} != "3.5" ] && [ ${PYTHON_VER} != "3.6" ] && if [ "$TRAVIS_OS_NAME" == "linux" ] && [ "$TRAVIS_SECURE_ENV_VARS" == true ] ; then conda install --yes -c omnia -c openeye propertyestimator; fi
 
   # Install Work Queue
   - wget https://raw.githubusercontent.com/leeping/forcebalance/master/tools/install-cctools.sh
@@ -164,7 +165,9 @@ script:
   - tar xvjf targets.tar.bz2
   - ForceBalance very_simple.in
   - cd -
-  - travis_wait 30 pytest --cov=forcebalance --cov-config=setup.cfg --durations=0
+  - pytest --cov=forcebalance --cov-config=setup.cfg --durations=0
+  # Allow tests to run for up to 30 minutes
+  # - travis_wait 30 pytest --cov=forcebalance --cov-config=setup.cfg --durations=0
   # - python test
   # - py.test -v --cov=eex/ --durations=5
 

devtools/conda-envs/test_env.yaml

@@ -21,7 +21,6 @@ dependencies:
   - swig
   - future
   - pymbar=3.0.3
-  - mdtraj
   - openmm
   - ambertools
   # The following two are not compatible with python 2.7 and 3.5, so they are conditionally installed in .travis.yml