Make floating_ip_bulk_destroy deallocate quota if not auto_assigned

The expected use case for floating_ip_bulk_destroy is to destroy
auto_assigned floating IPs, for which no quota is used so no quota
needs to be recovered.  But it can also be used to destroy other
(not auto_assigned) floating IPs, in which case the previously used
quota was not recovered.  This fixes the quota leak in that unusual
case.

Closes-Bug: #1254174

Change-Id: Ibff80d9ebac8d4422e401909033da12d9ec0b593
Do not set root device for libvirt+Xen

Currently we are setting the root device for Xen when using libvirt.
When a user is booting an image that contains a full partitioned disk it
fails, since the root device will be passed as "root=/dev/whatever" as
the cmdline to the booting kernel.

Closes-Bug: 1253626
Change-Id: Ia5e3ee8891759c68ee51b219d1a7f80d0afbeffc
Test guestfs without support for close_on_exit

A previous commit, fd621ef05a024b8319f2c67f7e5c084b9ab77755, fixed support for
versions of libguestfs that did not support the close_on_exit parameter.  This
patch adds unit test coverage for that code path.

Change-Id: Ic3cc0057e24ac00e6435a9555a19c076ddc9b02e
Related-Bug: #1271562
Related-Bug: #1261475
Remove tox locale overrides

* tox.ini: The LANG, LANGUAGE and LC_ALL environment overrides were
introduced originally during the testr migration in an attempt to be
conservative about the possibility that locale settings in the
calling environment could cause consistency problems for test runs.
In actuality, this should be unnecessary and any place where it does
cause issues ought to be considered an actual bug. Also, having
these in the configuration actively causes older pip to have
problems with non-ASCII content in some package metadata files under
Python 3, so drop it now.

Change-Id: I5353dd318ce0bfdc85d6468750fb4c2a2690cde1
Closes-Bug: #1277495
Merge "Do not set root device for libvirt+Xen"
Merge "Make floating_ip_bulk_destroy deallocate quota if not auto_assigned"
Merge "Test guestfs without support for close_on_exit"
Merge "Remove tox locale overrides"