build: remove scripts and makefile

Multi-stage docker builds and Quay.io build triggers can take care of
official builds. The Makefile is just absurd and has been replaced with
some documentation in the README.

Author: crawford

Dockerfile

@@ -1,8 +1,11 @@
-FROM scratch
-MAINTAINER CoreOS
+FROM golang as build
+WORKDIR /go/src/github.com/coreos/container-linux-userdata-validator/
+COPY . .
+RUN CGO_ENABLED=0 go build -o validate ./...
 
-EXPOSE 80
-WORKDIR /opt/validate
-ENTRYPOINT ["bin/validate"]
 
-ADD bin/validate /opt/validate/bin/validate
+FROM scratch
+WORKDIR /opt/validate/bin
+EXPOSE 80
+CMD ["./validate"]
+COPY --from=build /go/src/github.com/coreos/container-linux-userdata-validator/validate .

Makefile

@@ -1,3 +1,16 @@
 # CoreOS Userdata Validator
 
 This code powers the public service at https://coreos.com/validate/.
+
+## Building
+
+The included multi-stage Dockerfile can be used to build working images. Just run the following:
+
+    docker build .
+
+## Updating dependencies
+
+The following glide commands can be used to update the dependencies of this project:
+
+    glide update --strip-vendor
+    glide-vc --use-lock-file --no-tests --only-code