* Do not show the drives on windows, if STORAGE_DIR is set.
* Do not show non-applicable buttons, whenever no files/directory
present in the storage directory.
* Showing dimmer under the warning messages for replace/delete.
* Select file type other than 'All Files' in create/replace mode.
Tweaked a bit by Ashesh.
selection, creation, upload/download files/directories resides on the
server side.
This will be useful for file selection/creation for different server
side utilites like pg_dump, pg_dumpall, pg_restore.
