Replace {{tags}} with environmental variables

parse-template.sh

for line in $(find . -iname '*.dtpl'); do
	config=${line%.dtpl}
	cp $line $config
	echo "Replacing '$config'"
	for key in $(cat $config | grep -o -P '({{[0-9a-z_-]+}})'); do
		ukey=$(echo $key | sed 's/.*/\U&/' | sed -e "s/{{//" | sed -e "s/}}//")
		val=$(eval "echo \$${ukey}")
		#echo "Tag: $key $ukey $val"
		if [ -n "$val" ]; then
			echo "- Setting $key from environment."
			sed -i -e "s/$key/$val/" $config
		else
			echo "- Setting $key to empty"
			sed -i -e "s/$key//" $config
		fi
		
	done
done