- a source's interval must be greater than 0: a source is turned off with
enabled, not with a zero interval, so JSCSourcesSource rejects an interval of
0 or less (its validate is promoted to each source's section);
- max_message_size rejects -1: JSCServerWebSocket rejects a max_message_size
of -1 (util.ByteSizeNoLimit), as a client could then exhaust the server's
memory;
- every setting documents what 0 or empty means (zero/none, no limit or a
default).
bwilliams