Improve configuration of threads and timeouts

All thread-pool size should be configurable pools size, at least for these:

• handshake pool
• hello pool (for now it is not using thread pool)
• Netty

Timeouts:

• echo timeout
• handshake timeout
• RIP, idle timeout
• RPC timeouts (propagate timeout from client of the RPC to not wait for the result from the Switch after timeout)