Add GO111MODULE=on into build-min

build-min.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 
 docker run -it --rm -v $(pwd)/mailbox_bin:/mailbox_bin toomore/mailbox:base    \
-    sh -c "go get -v ./...;
+    sh -c "GO111MODULE=on go get -v ./...;
            cp /go/bin/* /mailbox_bin;"
 
 docker build -t toomore/mailbox:cmd -f ./Dockerfile-min ./