Remove env from rootwrap filter

Remove env from rootwrap filter

Allowing 'env' as a CommandFilter is similar to
allowing '/bin/bash', which makes all of rootwrap pointless.
Use EnvFilter instead. Change corresponding commands
that use env for setting C locale and adjust rootwrap
filters accordingly.

Several commands that output information that is
parsed as input by cinder change their behavior
based on the environment locale, which is depending
on local system settings. The code is however only
able to parse in C locale, so enforce that one.

Closes-Bug: #1269958

Change-Id: Ie1463e608c80204c7a8906efb95899a66aa733da