Since commit

3b50b276 "Optional reconnect functionality"

there is a config option named ask_reconnect_on_crash.
It asks the client to reconnect to the server if the server crashed.
It has been implemeted and works, but due to a function parameter not
being passed it never showed effect. This patch adds the parameter
and fixes the bug.

Also fixes the `reconnect` option of minetest.request_shutdown being ignored.