Add a script to ensure new lines exist in all files.

tools/ensure-new-lines.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -e
+
+git ls-files -z | while IFS= read -rd '' f
+do
+  if file --mime-encoding "$f" | grep -qv binary
+  then
+    tail -c1 < "$f" | read -r _ || echo >> "$f"
+  fi
+done