Raising glance logging levels

This change complements glance change #106776 by raising some logging
levels and fixing some of the translations of logging.

Related to bp refactoring-glance-logging
Closes-Bug: #1336955

Change-Id: Ib547f4603025ebe4f6c055779032ab4064784490
Change Glance to use i18n instead of gettextutils

Changing all Glance files to use i18n instead of gettextutils for log
translations.

Finishes bp refactoring-glance-logging

Change-Id: I90d6ab4f7e09f4e7591921f9526de6370ebdb789
Move from using _ builtin to using glance.i18n _

The builtin _ should not longer be used.  Instead _
should be explicitly assigned from glance.i18n.

This patch does the following:
  (1) adds these explict assignments to any
      glance file that was missing them,
  (2) removes the defintion of _ as a builtin from
      tox.ini so that a pep8 failure will occur
      if _ is not defined,
  (3) removes calls to install().

This removes the last direct use of gettextutils by glance.
The indirect uses, via openstack/common, will be removed
in the next sync with oslo.

Change-Id: Ie54e8a67e747e022cc01022dfad35d89686bdfc4
Merge "Raising glance logging levels"
Merge "Change Glance to use i18n instead of gettextutils"
Merge "Move from using _ builtin to using glance.i18n _"