lint: enable custom linters from go-lint project

ops/lint.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env sh
+
+set -e
+
+SCRIPT_DIR=$(cd "$(dirname "$0")" && pwd)
+PROJECT_ROOT=$(cd "$SCRIPT_DIR/.." && pwd)
+cd "$PROJECT_ROOT"
+
+./ops/build-lint.sh --if-needed
+GOLANGCI="./bin/golint"
+
+echo "Linting $(go list ./... | wc -w) packages"
+
+# Catches config keys in the wrong place, which are otherwise silently ignored.
+"$GOLANGCI" config verify
+"$GOLANGCI" run $@