wearemolecule/damage — pull request #13 by adamstrickland (2014-08-11 20:50:58+00:00)
Title: Adding support for to no-spam ICE during it's maintenance window

ICE has a maintenance window during which time FIX clients are expected to *not* send heartbeats as noted [here](https://www.theice.com/productguide/Search.shtml?tradingHours=). Currently, that window is:

- 18:30 - 19:30 Mon - Thu
- 18:30 Friday - 17:00 Sunday

This PR abstracts the `Damage::Client`s repeated async call away from `#send_heartbeat` to `#tick!`. The IceClient then overrides `tick!` to handle ICE's maintenance window.