CRM-14098 Membership reminders: don't exclude people who inherit other memberships...

CRM-14098 Membership reminders: don't exclude people who inherit other memberships (#12510)

* CRM-14098 Membership reminders: don't exclude people who inherit other memberships

* Membership reminders: test had two reminders with same name, differing params

* CRM-14098 Membership reminders: test for inherited members

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* CRM-14098: Scheduled reminders silently skipped for contacts with a non-permissioned relationship associated with ANY inherited membership type
  https://issues.civicrm.org/jira/browse/CRM-14098

* Membership reminders: comments to document some shaky assumptions

* CRM-14098 Membership reminders: fix relies on joins, causing DB error on repeat

* CRM-14098 Membership reminders: missing alias on date field

* CRM-14098 Reminders test: explicitly make emails primary