Handle better situation where changing email address to address of existing account with different casing.

If the account email has different casing to the supplied email, update the account to match the supplied email. This ensures Drupal and Persona are in agreement.

(cherry picked from commit 5f4bf1b0)

Conflicts:
	config/persona.settings.yml
	lib/Drupal/persona/Form/AdminForm.php
	persona.module

Issue #2097727 by jamsilver, jbrown: Drupal site install fails with a Fatal error with any install profile which depends on this module.

(cherry picked from commit a8ad5f03)

(cherry picked from commit 1f651239)

(cherry picked from commit 7d85e374)

This reverts commit 8fe05b33.

These variables are defined during site install.

This reverts commit 46ad121a.

It's entirely proper to have PHP warnings in response to bad data.

This reverts commit 45d2e85b.

SERVER_NAME is not necessarily the hostname that was in the request.

This reverts commit 0804a5e5.

It is not correct to use SERVER_PORT as the web server port is not necessarily the port the browser requests.