FreeNAS Code

Provide better diagnostic output when creating a home directory fails.

Add a safety belt to ensure that the user doesn't put his/her home directory under a subdirectory on the /mnt memory disk.

Make sure the nut daemons are dead. This closes a potential issue where nut stays up and running even after the service sliders claim things are off.

Don't reimport errno.

Fix a typo.

Simplify mntlock acquisition statements and simplify loops.

Fix the format string I added to volume_detach.

Rename volume_export to volume_detach to be more generic [1].
More 'renaming' needs to occur, but this will be an 8.2+ thing,
not an 8.0.3 thing (this is being done to avoid thrashing
dlavinge).

Mash zfs_export into volume_detach because it was only one
command.

Iterate through commands in a loop and stop at any errors to
ensure that things can be cleaned up at a later point in time
if something fails.

Document desired behavior and requirements.

1. Requested by jpaetzel.

try to catch MiddlewareError exceptions in django middleware instead of case by case

sysctl calls don't need to be printed out on the command line.