workflow 6.x-1.4

Changes since DRUPAL-6--1-3:

• SA-CONTRIB-2010-023, fix filtering of [workflow-current-state-log-entry] token when workflow is used together with Token module
• #593912 by jweowu: standardize hook altering
• #690860 by thekevinday: fix PHP 5.3 call by reference error
• #428376 by dman, Benedict Steele, Alan D.: add hook_content_extra_fields()
• #370111 by NickSI, crea, klausi, hefox, miro_dietiker: Rules integration for workflow. Incorporates #472966 by klausi: Implement subsequent runs control
• check_plain() username and mail tokens. These are already sanitized on input by user_validate_mail() and user_validate_name().
• #729544 by dooug: add API function to retrieve workflow state name
• #729610 by dooug: return sid from workflow_execute_transition()
• #515458 by M_Z: workflow trigger assignments not being deleted
• #253711 by sharplesa: pass node as action object to system actions
• #730482 by jvandyk: do not suggest reassignment to other states when last state in a workflow is deleted
• #327144 by prof1337: correctly assign token values in various scenarios
• #652406 by Josh Waihi: make workflow scheduled state changes possible from comments
• #653260 by franz: fix typo in documentation