forwarder as a fallback in circuit breaker

[mgjv]

We've been looking at vulcand for our environment, but we're missing some functionality that we'd like to have.

We have a pattern of falling back to a second copy of a service (in another region) before giving up, i.e. the pattern is:

1. try the local (read) service
2. if fail (using circuit breaker) try the remote (read) service
3. if fail -> error

Ideally, we'd handle that in the internals of vulcand, with a second backend or so, but that seems like a lot more change than necessary. We think it should be possible to make a new circuit breaker fallback using the forwarder in oxy that could do this job.

If we were to implement this, is there an appetite to accept a pull request of that nature?

[mgjv]

also see #88

[klizhentas]

yes, go for it