Add text.dat lines for "All" and the List key ('L'), used in quoting

The internal line editor's quoting feature add some hard-coded strings ("Done" and "All") and the (L)ist key was hard-coded. Use the text.dat string (new and pre-existing) for these now.

Also, use the new sbbs_t *_key() methods for referencing the configured key bindings (via text.dat) for these common key-stroke commands.
Convert the text.dat strings for keys (e.g. YNQP) to uppercase always as well.