Add handling of multiple sproxyd connectors

[ghost]

As of now, we only handle one, which is terribly error-prone, we'll want to get an array of connectors.

[JordanP]

It's common to have one sproxyd connector on http://node1:81/proxy/bpchord and another on http://node2:81/proxy/chordbp. With this commit because the "path" is shared across all the connectors, it's not possible.

It's a detail though :) But it might be worth to consider it as an enhancement.

[ghost]

We specifically only use /proxy/arc at the moment with the lack of erasure coding on the network level, but yeah, this could be done easily.