Add a working Travis pipeline

scripts/jsonnet/Dockerfile

@@ -0,0 +1,19 @@
+FROM golang:1.11-stretch
+
+ENV JSONNET_VERSION 0.12.1
+
+RUN apt-get update -y && apt-get install -y g++ make git jq && \
+    rm -rf /var/lib/apt/lists/*
+RUN curl -Lso - https://github.com/google/jsonnet/archive/v${JSONNET_VERSION}.tar.gz | \
+    tar xfz - -C /tmp && \
+    cd /tmp/jsonnet-${JSONNET_VERSION} && \
+    make && mv jsonnet /usr/local/bin && \
+    rm -rf /tmp/jsonnet-${JSONNET_VERSION}
+RUN go get github.com/brancz/gojsontoyaml
+RUN go get github.com/campoy/embedmd
+RUN go get github.com/jsonnet-bundler/jsonnet-bundler/cmd/jb
+
+RUN mkdir -p /go/src/github.com/coreos/kube-prometheus
+WORKDIR /go/src/github.com/coreos/kube-prometheus
+
+RUN chmod -R 777 /go