Add a way to add and search private and org private entries

[crufter]

Terminal interface ideas:

borg my "query" - queries personal private entries
borg our "query" - queries org private entries if the user only belongs to one organization
borg uber "query" - queries org private entries for Uber if the user belongs to that org. It is a regexp of *uber* so...

If a user is member of UberIceCream and UberEats organization to not be ambivalent he has to specify

borg eats "query" or borg cream "query" etc to match exactly, otherwise borg throws an error.

cc @jeremyletang

For now we should keep every org in separate indexes on the backend. This prevents us from searching across multiple orgs but that's fine for now.