set timeout explicitly in node proxy for rest server
set timeout explicitly in node proxy for rest server

As part of #395, "warm-up" issue...

Ensure proxy tries to stay open waiting for middle-tier requests for
31 seconds, giving it as much time as we can to respond.

omkarudipi/marklogic-samplestack,omkarudipi/marklogic-samplestack,marklogic/marklogic-samplestack,dmcassel/marklogic-samplestack,laurelnaiad/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,supriyantomaftuh/marklogic-samplestack,laurelnaiad/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,omkarudipi/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,dmcassel/marklogic-samplestack,marklogic/marklogic-samplestack,marklogic/marklogic-samplestack,dmcassel/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,omkarudipi/marklogic-samplestack,dmcassel/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,laurelnaiad/marklogic-samplestack,laurelnaiad/marklogic-samplestack,marklogic/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack