Start the key generation between two dummy device on the fly

[kaiduanx]

Now QNL layer starts the key generation process by invoking startNode when OpenQKDNetwork node starts running, and we run dummy driver before starting OpenQKDNetwork. We need to change the behaviour as below,

Assume Node A and Node B, there is a link between A and B, and there is a dummy driver on node A and node B respectively. Node A notes node B as peer, and dummy driver on node A notes dummy driver on node B as peer.

1. When SiteAgent A detects dummy driver A is registered, it queries the peer SiteAgent B to check if the peer dummy driver B is registered by making getDevice GPRC call to SiteAgent B.
2. If the peer dummy driver B is registered on peer site agent B, site agent A starts the key generation by invoking startNode.

In this way, we do not need to run dummy driver before running OpenQKDNetwork.

The node with smaller id starts the key generation process. For the case A and B, node A invokes the startNode.