Make defaults the highest-priority conda channel

.travis.yml

@@ -51,12 +51,12 @@ before_install:
  - conda config --set always_yes yes --set changeps1 no
  - conda update conda
  - conda config --add channels conda-forge
+# Make defaults again the highest priority channel
+ - conda config --add channels defaults
 # setuptools >= 45 no longer supports Python 2
  - if [[ $TRAVIS_PYTHON_VERSION == 2.7 ]]; then SETUPTOOLS_VERSION="<45"; else SETUPTOOLS_VERSION=""; fi
  - conda create -n test-environment python=$TRAVIS_PYTHON_VERSION "numpy>=1.16" scipy matplotlib numexpr "setuptools$SETUPTOOLS_VERSION" pip "cython>=0.20" pytest
  - source activate test-environment
-#Switch to conda defaults python, because conda-forge python has issues with gcc compiler similar to https://github.com/conda/conda/issues/6030
- - conda install python=$TRAVIS_PYTHON_VERSION -c defaults
 #Download corrections for some tests
  - curl -O https://github.s3.amazonaws.com/downloads/jobovy/galpy/galpy-dfcorrections.tar.gz
  - tar xvzf galpy-dfcorrections.tar.gz -C ./galpy/df/data/
@@ -72,8 +72,6 @@ install:
 # pynbody, install deps with conda as much as possible
  - if $REQUIRES_PYNBODY; then conda install h5py pandas pytz; fi
  - if $REQUIRES_PYNBODY; then pip install git+git://github.com/pynbody/pynbody.git; fi
-# pytz install (I think) seems to downgrade certifi above, so update to newer version
- - if $REQUIRES_PYNBODY && [[ $TRAVIS_PYTHON_VERSION == 2.7 ]]; then conda update certifi; fi
  # clone my version of the torus code, don't do this for one test, to make sure the code installs without the torus code
  - if [[ $TEST_FILES != 'tests/test_evolveddiskdf.py tests/test_jeans.py' ]]; then git clone https://github.com/jobovy/Torus.git galpy/actionAngle/actionAngleTorus_c_ext/torus; fi
  - if [[ $TEST_FILES != 'tests/test_evolveddiskdf.py tests/test_jeans.py' ]]; then cd galpy/actionAngle/actionAngleTorus_c_ext/torus; fi