Fixes #244
Fix scan command for CLI.
Merge branch 'issue#244_disks_scan_cmd' of git://github.com/aliamir/rockstor-core into aliamir-issue#244_disks_scan_cmd
Update disk API to make the scan an explicit command. Also remove the trailing
slash for url endpoints.
Update disk include in the main urls file
Update webui for backend disk api changes
Update disks console for backend api changes
Fixes #284.

Fix the memory consumption problem by making debug = false for prod and true
for dev.
Fixes #284

Use zmq sink instead of python queues between smart manager processes. It is
much faster and consumes less memory over all.
Merge pull request #288 from schakrava/issue#284

Issue#284
Merge branch 'master' into aliamir-issue#244_disks_scan_cmd
Update disk model to keep track of offlined disks
Add low level system code to detect drives used for root fs.
Flag offlined disks during scan/rescan
Update setup disks front end code according to new disk api
Don't allow disks with partition table to be used during pool creation.
Add delete API for offline'd disks.
update api call to return server side error wrapped in an exception.
Add function decorator for top level api error handling. This decorator can be
used by all cli methods calling api_call and the decorator will take care of
printing any backend errors.
Update frontend disk template for offlined and partitioned disks -- mostly stub.
Update disks console to use api_error handler