CRM_Core_BAO_CustomField - Format
CRM-13027 - api_v3_CustomFieldTest - Also check getfields for the contact types

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* CRM-13027: Default getFields returns irrelevant custom-data fields
  http://issues.civicrm.org/jira/browse/CRM-13027
CRM-13027 - Fix bad results from getFields:

 * If entity is not extendable, then field list should be empty (not all).
 * If entity is blank, then throw an error.

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* CRM-13027: Default getFields returns irrelevant custom-data fields
  http://issues.civicrm.org/jira/browse/CRM-13027
Merge pull request #1564 from totten/master-getfields-fix

CRM-13027 - Fix handling of custom-data in getfields API