Limiting queued message depth purely based on message count is hard to
control for memory constrained devices. The size of messages can vary
wildly, from a few bytes, to a few kilobytes. Support a new
max_queued_bytes option, and drop packets when the first limit is
reached. Option defaults to 0 (disabled) by default.
Support also a max_inflight_bytes variable, with similar behaviour.
Fixes (partof) https://github.com/eclipse/mosquitto/issues/100
This pulls up some helper routines for calculating whether to allow
inflight or queuing, resolving some inconsistences in connection
resumption.
Signed-off-by: Karl Palsson <karlp@etactica.com>
