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Avoid deep indentation, use more levels of headings instead.
Fix refs to geonode.utils.ogc_server_settings

Fixes #1455
Import the Layer model into geonode.geoserver.signals.
Add missing imports to the Geoserver views.
Bump Django.
Include uploaded file in paver reset
Simplified handling of thumbnails.

* Added tests for thumbnails in Layers and Maps.
* Removed ThumbnailMixin class and just created methods in ResourceBase.
* Removed need to call save again in catalogue or mess with signals.
* Added logic to return the link to the WMS image in thumbnail if WMS is not yet available during upload.
* Uploads are now around 2x faster.
Fixed map saving.
Missing imports
Pass in the style name as a string vs an object when settings styles on layers.  Fixes #1456.
Fix typo'postigs'

Fixes #1459.
Fixes #1458
Some more doc tweaks
Small fixes to thumbnails.

* Return the .url property vs the layer object.
* The geoserver pre-save signal should user filter vs get to lookup thumbnails.
* Add missing gs_uploader import to the upload models.
Refactor the last commit to fix broken tests.
Moves geoserver-specific url routes to the geoserver app.

* acls, resolve_user and layer_batch_download have been moved to /gs/acls, gs/resolve_user, and gs/download.
* The old routes (using the /layer prefix) still work, but should be removed once legacy code is updated.
Remove the duplicate forward slash from the gs/rest/layers url route. Fixes #1457.
Merge pull request #1460 from garnertb/gs-layer-views

Moves geoserver-specific url routes to the geoserver app.
Tidying while reading

Indentation fixed on one section too.
Tidying while reading

Avoid deep indentation, use more levels of headings instead.