Remove trusted facts from indirector

Data coming from PuppetDB will include trusted facts as a structured
fact under the name "trusted". Puppet expects that it is the source of
trusted facts and so seeing these trusted facts included in results from
the indirector causes Puppet runs to fail. Previously this only happened
when there was some issue reading facts from cache (hence going to
PuppetDB to get the most recent copy). Current behavior is no longer
going to cache and is always going to PuppetDB, which always fails since
PuppetDB will include trusted facts.

This commit removes trusted facts from indirector responses.