Sync gettextutils from Oslo

Update gettextutils as a dependency for RPC updates

Requires changes within Cinder as well for
"get_localized_message" -> "translate" method rename.

221c37d Allow the Message class to have non-English default locales
0e1af5b Implementation of translation log handler
f5686b1 Merge "Translation Message improvements"
8b2b0b7 Use hacking import_exceptions for gettextutils._
2cfc1a7 Translation Message improvements
45658e2 Fix violations of H302:import only modules
12bcdb7 Remove vim header

Oslo version:
7a51572 Merge "Implement cache abstraction layer"
Date:   Wed Jan 15 19:31:16 2014 +0000

Change-Id: I979114dbebfe2368b071cc6c18951da227b6f74a
Merge "Sync gettextutils from Oslo"