GEOT-4468 backported support for custom outputFormat for WFS 1.1.0 in WFSDataStore
Merge pull request #244 from mbarto/geot_4468_9x

GEOT-4468 backported custom outputFormat support for WFS 1.1.0 in WFSDataStore
Merge branch '9.x' of https://github.com/geotools/geotools into 9.x
improved PNG writing for ImageWorker