Added wxDirDialog functionality.
Added wxDirDialog functionality.

ivoflipse/devide,nagyistoce/devide,fvpolpeta/devide,fvpolpeta/devide,ivoflipse/devide,chrisidefix/devide,zhangfangyan/devide,chrisidefix/devide,zhangfangyan/devide,nagyistoce/devide