This includes prim count, script count, avatar count, etc.
Information is currently the same as "show stats", though show stats can only show one scene at a time because it listens for the latest outgoing stats packet (a bad approach that needs to change).
Might be better to tie this module into the other stats module to display arbitrary stats rather than fetching directly from scene.SimStatsReporter.
Console command is "show scene" because "show region" already exists for the grid service, which is unfortunate.
Might need to make a distinction between "scene" relating to a live scene and "region" relating to more static region data (url, coords, etc.)
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