File browser fixes.

Fix some errors on file browser when the server is Windows:

* Create folders on subfolders
* Update file status on subfolders
* Download files
NDVI stats fixes.

Allow to deploy geobatch instance on windows servers.
Merge pull request #49 from alediator/windows_fixes

File browser fixes.
Merge pull request #50 from alediator/nrl_windows_fixes

NDVI stats fixes.