Limit iNat imports to the user's own Observations

[JoeCohen]

But see #2312. We do not want to do this if foray recorder needs to import other users' obss.

Restrict the iNat observations which an MO user can import to the user's own iNat obss; At the moment, an MO user can import other people's iNat obss (but just the public data).

I don't know how to do this. Might need to require the MO user to enter iNat user_id and password.

[JoeCohen]

Could I do something like in authenticate get the current user. See https://api.inaturalist.org/v1/docs/#!/Users/get_users_me Add that user's user_login or user_id to the search request, so that we return only that user's obss

[JoeCohen]

This issue incorporated into #2340