Fix phpdoc problems (#85)

.travis.yml

adminlib.php

classes/action.php

classes/entity/process.php

classes/entity/step_subplugin.php

classes/entity/subplugin.php

classes/entity/trigger_subplugin.php

classes/entity/workflow.php

classes/event/process_proceeded.php

classes/event/process_rollback.php

classes/event/process_triggered.php

classes/form/form_step_instance.php

classes/form/form_trigger_instance.php

classes/form/form_upload_workflow.php

classes/form/form_workflow_instance.php

classes/local/backup/backup_lifecycle_workflow.php

classes/local/backup/restore_lifecycle_workflow.php

classes/local/data/manual_trigger_tool.php

classes/manager/backup_manager.php

classes/manager/delayed_courses_manager.php