v2.4

New Features

• router match rules now support a validate clause to do data
  filtering, Issue #228,
  Issue #142,
  Issue #121,
  Pull #127,
  Pull #87.

Bugfixes

• server connection errors are no longer endlessly repeated
• Issue #240
  'include' directive doesn't care about rewrites.
• Issue #241
  XXX characters being prepended to metrics when sent via UDP
• Issue #204
  relay is sending data randomly while kill -HUP happens