CRM-20868, set invoice_number at contribution->create, not invoice creation
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* CRM-20868: set invoice_number at contribution->create, not invoice creation
https://issues.civicrm.org/jira/browse/CRM-20868
CRM-20868, style fix
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* CRM-20868: set invoice_number at contribution->create, not invoice creation
https://issues.civicrm.org/jira/browse/CRM-20868
CRM-20868, fixed style error
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* CRM-20868: set invoice_number at contribution->create, not invoice creation
https://issues.civicrm.org/jira/browse/CRM-20868