Synced jsonutils and its dependencies

The sync includes change that drastically enhances performance on Python
2.6 with fresh simplejson library installed.

The latest git commit in oslo-incubator:
- 109e325eec054aefe4fcef4b928a46a6d7247e05

List of synced commits:
* gettextutils.py:
  - de4adbc4: pep8: fixed multiple violations
* importutils.py:
  - 1173e469: Remove ValueError when accessing sys.modules
* jsonutils.py:
  - 0d7296f6: Add kwargs to jsonutils.load(s) functions
  - 18f2bc1b: Enforce unicode json output for jsonutils.load[s]()
  - 9e5a3938: jsonutils.load() accepts file pointer, not string
  - a6b2aecf: On Python <= 2.6, use simplejson if available
* strutils.py:
  - 8a0f5678: Remove str() from LOG.* and exceptions
  - fd18c288: Fix safe_encode(): return bytes on Python 3
  - 302c7c80: strutils: Allow safe_{encode,decode} to take bytes as input
* timeutils.py:
  - 250cd88c: Fixed a new pep8 error and a small typo

Change-Id: Ib3dc0b713ed90396919feba018772243b3b9c90f
Closes-Bug: 1314129
Merge "Synced jsonutils and its dependencies"