Add Akka specific config for CI environment

These config files provides specific settings to those projects using
Akka in order to dilate the timeouts on heavily loaded machines (e.g.,
Jenkins server).

The specific config files may be used by passing the argument
`-Dconfig.resource=application-ci.conf` to sbt.

This fixes bug #104.
Make BuyerExchangeActor to receive initialization message
Make HandshakeActor to receive an initialization message
Make PeerActor to receive an initialization message
Make MessageGateway to receive an initialization message
Make HandshakeArbiterActor to receive an initialization message