Fixes #5148 - Permit the add of lines in a section from a INI file even if the section does not exist

Fixes #5148 - Permit the add of lines in a section from a INI file even if the section does not exist

cf http://www.rudder-project.org/redmine/issues/5148
I'm not sure about the 'create => "true"'. If an INI file does not exist, no need to force its creation for a section/line.