run tests with and without gx on CI

.travis.yml

@@ -8,15 +8,24 @@ go:
 # setting the GOARCH directly doesn't work, since the value will be overwritten later
 # so set it to a temporary environment variable first
 env:
-  - TRAVIS_GOARCH=amd64
-  - TRAVIS_GOARCH=386
+  - TRAVIS_GOARCH=amd64 GX=true
+  - TRAVIS_GOARCH=amd64 GX=false
+  - TRAVIS_GOARCH=386 GX=true
+  - TRAVIS_GOARCH=386 GX=false
 
-# second part of the GOARCH workaround
-# now actually set the GOARCH env variable to the value of the temporary variable set earlier
 before_install:
-  - make deps
-  - export GOARCH=$TRAVIS_GOARCH
   - go env # for debugging
+  - if [ $GX == "true" ]; then 
+      echo "using gx";
+      make deps;
+    else
+      echo "not using gx";
+      make testutils;
+      go get -u -t ./...;
+    fi
+  # second part of the GOARCH workaround
+  # now actually set the GOARCH env variable to the value of the temporary variable set earlier
+  - export GOARCH=$TRAVIS_GOARCH
 
 # see https://github.com/travis-ci/travis-ci/issues/8361#issuecomment-350090030
 before_script: