remove obsolete code
fixes to setdefaults, CRM-12970

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* CRM-12970: civicrm_price_field_value not removed for discount price set
  http://issues.civicrm.org/jira/browse/CRM-12970
minor fix, CRM-12970

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* CRM-12970: civicrm_price_field_value not removed for discount price set
  http://issues.civicrm.org/jira/browse/CRM-12970
Merge pull request #1363 from kurund/CRM-12970

CRM-12970, fixes to setdefaults discount fees