[awips2-users] Enabling convectprob plugin

I was able to ingest the CIMSS ProbSevere into edex, but serving it to
cave clients is not working.  The error I get is this:

com.raytheon.uf.viz.core.exception.VizException:
com.raytheon.uf.common.inventory.exception.DataCubeException:
com.raytheon.uf.viz.core.requests.ServerRequestException: Plugin
convectprob is not registered with the PluginRegistry

I'm running edex version 18.1.1-6, and I'm assuming the plugin only
needs to be enabled on the server.