work around jsonschema version in npm (fix)
work around jsonschema version in npm (fix)

The version of jsonschema that is coming out of npm is fouled up.

Reference the repository at the current commit in package.json, instead.

marklogic/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,laurelnaiad/marklogic-samplestack-old,dmcassel/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,supriyantomaftuh/marklogic-samplestack,laurelnaiad/marklogic-samplestack,clockworked247/marklogic-samplestack,marklogic/marklogic-samplestack,omkarudipi/marklogic-samplestack,omkarudipi/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,laurelnaiad/marklogic-samplestack-old,marklogic/marklogic-samplestack,laurelnaiad/marklogic-samplestack,marklogic/marklogic-samplestack,dmcassel/marklogic-samplestack,omkarudipi/marklogic-samplestack,omkarudipi/marklogic-samplestack,ryanjdew/discovery-app-w-samplestack,supriyantomaftuh/marklogic-samplestack,dmcassel/marklogic-samplestack,dmcassel/marklogic-samplestack,laurelnaiad/marklogic-samplestack,supriyantomaftuh/marklogic-samplestack,laurelnaiad/marklogic-samplestack,clockworked247/marklogic-samplestack