Document activity_who and related options for SIP user activity tracking

[Jeff Godin]

Commit aebf4a5 in 2012 introduced support for SIP actions to generate user activity records.

With this support came new configuration options for the SIPServer config file:

activity_who (associated with <login> or <institution>)

default_activity and force_activity_who (associated with <implementation_config>)

This feature and these options appear to have no current documentation.

[Michele Morgan (mmorgan)]

Adding a link to an IRC discussion for those seeking more information:

http://irc.evergreen-ils.org/evergreen/2017-12-04#i_336286

As an example, we set up an activity type to track OverDrive logins using SIP authentication.

In oils_sip.xml:

<login id="overdrive" password="<REDACTED>" activity_who="overdrive" institution="noble"/>

Pertinent values in config.usr_activity_type:

ewho: overdrive
ewhat: verify
ehow: sip2
label: OverDrive Login