travis: fix gocc installation
#!/bin/bash
-go get github.com/goccmack/gocc
+set -ex
+
+# TODO(kortschak): Replace this with versioned go get when
+# all our supported versions of Go support it.
+mkdir -p $GOPATH/src/github.com/goccmack
+git clone https://github.com/goccmack/gocc.git $GOPATH/src/github.com/goccmack/gocc
cd $GOPATH/src/github.com/goccmack/gocc
git checkout $1
go install
