ci: add initial config for gitlab CI

Just checks linting, and build/test.

.gitlab-ci/check_gofmt.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+
+files="$(gofmt -l .)"
+
+[ -z "$files" ] && exit 0
+
+# run gofmt to print out the diff of what needs to be changed
+
+gofmt -d -e .
+
+exit 1