Make announceStopViaConsole configurable

Continuation of #10: the proposed enhancement here is to read a list of commands, perhaps from a file at the root of the server to execute a custom set of shutdown commands

The current implementation uses a single 'say' command, our use-case is a preference for 'title' commands at intervals before a shutdown.

c.c. @morrissimo

Start by locating the current shutdown entry point that issues the single `say` command, then review how configuration could be read from a file at the server root. Done means users can provide a custom list of shutdown commands, including repeated `title` commands at specified intervals, with the behavior covered by appropriate tests.

Written by the indexing model from the issue text.