Handle for data_dir_zip not being found
Ass filter option and pass to gs_slurp
Set cache time to 0 from settings
Add options for filtering by store or by a filter string in updatelayers
Merge branch 'master' of github.com:GeoNode/geonode into updatelayers-work
Merge pull request #925 from jj0hns0n/updatelayers-work

Updatelayers work