Make sure gomodule is enabled for CI that puts the repo in gopath

.travis.yml

 language: go
 go:
   - 1.11
+env:
+  - GO111MODULE=on
 script:
   - ./build.sh

appveyor.yml

@@ -23,6 +23,7 @@ install:
 
 build_script:
   - set GOBIN=%CD%/bin
+  - set GO111MODULE=on
   - go install -v ./cmd/...
 
 artifacts:

build.sh

 #!/bin/bash
 
-GO111MODULE=on GOBIN=$PWD/`dirname $0`/bin go install -v ./cmd/...
+GOBIN=$PWD/`dirname $0`/bin go install -v ./cmd/...