Updates some modules from oslo-incubator

Updates context, gettextutils and timeutils modules.

Last oslo-incubator commit
fd90c34a914ef98e0c7ccdbf823d9b6d04aa436b

Change-Id: I1e4335578b517ca16adc386860ac4fc579f57f5c
Related-Bug: #1290849
Merge "Updates some modules from oslo-incubator"