Anonymous online contributions should check for duplicate contacts and send alert to admin if possible dupe(s) are detected

Currently we never check to see if a possibly matching contact exists when anonymous users make an online contribution. However, we DO check this for "on behalf of organizations" - and if we detect a possible match we send an alert email to the site admin.

This seems like the right thing to do for contributors as well:

• Add a check using default Individual Strict matching rule
• If one or more matches detected, fire off an email to the site admin indicating that a contribution was recorded and a contact record created - but that the contact is possibly a duplicate of .... (provide list of dupe match contact display name or names and links to their records).

NOTE: This check is for alert purposes only! The main processing logic is unchanged - we always create a new contact and new contribution record for anonymous contributions.

---- Original post ----
Dedupe does not merge duplicate contacts when using the contribute module, but shows matching contacts when run manually (Individual Strict). I experienced this error on a site currently in production and was able to duplicate the issue in the demo site: See Merge Contacts > Individual Strict, the first record "Philip Van Drunen" was created manually, the second using the public contribution form with a profile that I created: http://drupal.demo.civicrm.org/civicrm/contribute/transact?reset=1&id=4