Update version 0.9.11 -> 0.9.12

Fixes
-----
* Fix bug in `DWaveCliqueSampler` chain strength formula

Author: arcondello

dwave/system/package_info.py

@@ -15,7 +15,7 @@
 # =============================================================================
 __all__ = ['__version__', '__author__', '__authoremail__', '__description__']
 
-__version__ = '0.9.11'
+__version__ = '0.9.12'
 __author__ = 'D-Wave Systems Inc.'
 __authoremail__ = '[email protected]'
 __description__ = 'All things D-Wave System.'