Rate Limiting plugin
====================

This ATS provides basic rate limiting functionality, it currently has two modes:

* As a remap plugin, it will limit the number of concurrent transactions
* As a global plugin, it will limit the number of concurrent TLS connections

TODO
====

This is still POC / MVP, and needs work. Here's a short list of ToDo items:

* We ought to have a YAML configuration, and YAML parser, for the SNI limiters.

* The global YAML configuration(s) also should be reloadable at run time. This
  likely is best done replacing the entire SNI selector, at which point care has
  to be taken when replacing the current selector, and when to delete it (ref-count?).

* The per-remap rules each creates its own queue processing continuation. This is
  pretty inefficient, and it would make sense to make a new TXN based selector, which
  keeps the list of all TXN limiters currently in used. Care has to be taken here when
  reloading remaps, to only remove limiters which are no longer needed (should be ok
  since the remap destructor only gets called after all ref-counts are zero).
