CRM-12877 - ReportInstance API - Fixes for testCreateSingleValueAlter
 * group_role
 * is_reserved
 * header
 * footer

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* CRM-12877: Provide api for creating report instances
  http://issues.civicrm.org/jira/browse/CRM-12877
CRM-12877 - ReportInstance API - Fixes for testCreateSingleValueAlter (report_id)

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* CRM-12877: Provide api for creating report instances
  http://issues.civicrm.org/jira/browse/CRM-12877
SyntaxConformanceAllEntitiesTest - Prettify optional error output
Merge pull request #1231 from totten/master-reportinstance-api

CRM-12877 - Fixes for single-value alteration