Api3 - Add uf_user contact search param

[colemanw]

Overview

Exposes another advanced search field to the api.

Before

Not available to search contacts with/without user records.

After

Available to search contacts with/without user records.

[civibot]

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[totten]

@colemanw FWIW, there is a way to search by username -- any API filter that accepts a contact ID can take @user:<name> instead:

# Find contact for user "demo"
cv api contact.get id=@user:demo

# Find activities created by user "demo"
cv api activity.get source_contact_id=@user:demo

# Create a note about user "demo" attributed to user "admin"
cv api note.create contact_id=@user:admin entity_table=civicrm_contact entity_id=@user:demo note='the best demo user ever' 

It's pretty flexible/general/simple, but I don't know an effective way to communicate its existence...

I like how this param is more discoverable, but it'd be a lot of work to reproduce for other use-cases.

[eileenmcnaughton]

@totten I am not even sure that syntax is in the api docs...