The scheduler library should have a delay before initiating a connection with master.

Currently, the scheduler library src/scheduler/scheduler.cpp does have an artificially induced delay when trying to initially establish a connection with the master. In the event of a master failover or ZK disconnect, a large number of frameworks can get disconnected and then thereby overwhelm the master with TCP SYN requests.

On a large cluster with many agents, the master is already overwhelmed with handling connection requests from the agents. This compounds the issue further on the master.