Pylint fixes for Brick iSCSI/LVM

Fixes a few of the more straightforward pylint errors
in these files.  (anomalous-backslash-in-string,
attribute-defined-outside-init, and bad-indentation)

Change-Id: Ic131717a83fe182fe578b63eccf364d300a8989c
Pylint fixes for GlusterFS driver

Remove unused 're' import
Remove unused parameter for _create_snapshot()

Change-Id: I40411b6206d282ae07c905faa44dcccecb45c120
Remove unused code from volume manager (reset_stats)

self._last_volume_stats appears to be unused, now that we don't
use _volume_stats_changed().  This means reset_stats() also does
nothing.

This triggered a pylint 'attribute-defined-outside-init' warning.

Change-Id: I4c4f7497e72f726f3430f90df61188bf2f1073c1
Merge "Pylint fixes for GlusterFS driver"
Merge "Pylint fixes for Brick iSCSI/LVM"
Merge "Remove unused code from volume manager (reset_stats)"