fixup! Try fixing #231 again: Return to using platform_python_implementation

Author: gsnedders

.travis.yml

@@ -16,10 +16,6 @@ cache:
 env:
   - USE_OPTIONAL=true
   - USE_OPTIONAL=false
-  - USE_OPTIONAL=false SETUPTOOLS=18.5
-  - USE_OPTIONAL=false SETUPTOOLS=20.2.2
-  - USE_OPTIONAL=false SETUPTOOLS=20.6.6
-  - USE_OPTIONAL=false SETUPTOOLS=20.10.0
 
 before_install:
   - git submodule update --init --recursive

requirements-install.sh

@@ -8,11 +8,6 @@ fi
 # Make sure we're running setuptools >= 18.5
 pip install -U pip setuptools>=18.5
 
-# Install specific version of setuptools, maybe
-if [ -n "$SETUPTOOLS" ]; then
- pip install "setuptools==$SETUPTOOLS"
-fi
-
 pip install -U -r requirements-test.txt
 
 if [[ $USE_OPTIONAL == "true" ]]; then