JCBC-347: Adjust observe intervals for better performance.

By decreasing the observe poll interval, better throughput on
intense replicateTo settings can be achieved. This can also be
modified through the Builder, but setting it to a lower value
should provide a better experience by default.

Also, the max poll cycles have been increased so together now
the max waiting time is 5 seconds.

Change-Id: I348aaa28ef9c2fea4161750178c1308be4231e7b
Reviewed-on: http://review.couchbase.org/28391
Reviewed-by: Michael Nitschinger <michael.nitschinger@couchbase.com>
Tested-by: Michael Nitschinger <michael.nitschinger@couchbase.com>