[C++] Extend internal TTL of libjoynr discovery proxy by 10s
[C++] Extend internal TTL of libjoynr discovery proxy by 10s

This prevents timeouts between libjoynr and the global capabilities directory.

Following assumptions are made:
 * the communication to the cluster-controller is way faster then the one from the
   cluster-controller to the backend (common case)
 * this value is greater then the TTL set on the cluster-controller side to communicate
   with the global capabilities directory
 * the cluster-controller uses as default value MessagingQos::default_ttl

Change-Id: If3a438a0d4159411281765388eb43fd049dadbed

bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr