CRM-12248 fix status msg (should reference Supervised dedupe rule instead of Unsupervised) and fix alert display to be one-at-a-time.

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* CRM-12248: Configure Event: Registration tab - ruleFields variable used to display alert for Allow multiple
  http://issues.civicrm.org/jira/browse/CRM-12248
Merge pull request #308 from davecivicrm/CRM-12248

CRM-12248 fix status msg (should reference Supervised dedupe rule instea...