* Add log_burst_limit_* options
On our ejabberd deployment we were sometimes seeing more than 500
msgs/sec of legitimate traffic, however this was getting silently
dropped. Provide config options to enable this limit to be configured
from the config file.
* Pass new logging vars in via ejabberdctl
Until now, when stopping the ejabberd container, Erlang is not gracefully
closed, Mnesia is not properly closed... exit code is 137.
With this change, when the container is stopped, Erlang receives the
SIGTERM signal, shutsdown, Mnesia database is properly closed, ...
and exit code is 0.