Adjust agent RMI timeouts and specify unit-suffix notation.

The agent RMI timeouts specified in server.conf have pretty much been a guess.  I don't know what the best values should be but I believe these values are more reasonable. 

**Long term**, I think we should probably re-implement the agent RMI timeouts leveraging more of the tasking system; doing interesting things in the PollingCommand (client); (some) timeout functionality and the relatively new cancellation functionality provided gofer.

Specifying the units just improves readability.