feat(pg_extract): script for extracting single database from dump (https://stackoverflow.com/a/48866503)

Author: kosheeta

pg_extract.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+# https://stackoverflow.com/a/48866503
+
+[ $# -lt 2 ] && { echo "Usage: $0 <postgresql dump> <dbname>"; exit 1; }
+
+sed  "/connect.*$2/,\$!d" $1 | sed "/PostgreSQL database dump complete/,\$d"