Abitliy for nodes to connect to multiple drivers

[lolocohen]

Description

Today, JPPF nodes can only connect to a single driver at a time. While this does not prevent HA capabiltiies in a JPPF grid, thanks notably to built-in failover features, it requires an external control mechanism for the grd to get back to its original healthy state, once unforeseen problems have been addressed. An example of such a contorl mechanism is illustrated in the GridFailover sample.

Expected benefits and drawbacks

We expect the feature to enable HA and failover transparently and instantaneously, without forcing the nodes to reconnect to a different driver to restore the initail grid state