Add helpful startup script for docker container

Not actually adding this to the container yet. Want to make sure
@matburt is okay with that first.

tools/docker/start_everything.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+
+/etc/init.d/postgresql start
+/etc/init.d/redis-server start
+#nohup mongod --smallfiles &
+
+(cd /tower_devel && make server &&
+/bin/bash)