heat : bump oslo-config version to fix import error

New oslo config patch causes services to fail to launch, with
"ImportError: No module named oslo.config", bumping to
oslo-config-2013.1b4.tar appears to fix the problem

fixes bug 1131135

Change-Id: I460564be19fc97bd54bb59c759c1148e7ead774b
Merge "heat : bump oslo-config version to fix import error"