ClassDecorators defined using original class names (without lowercase)
Verbose option in __call__ now toggles logging from debug to message
Calls to topo.sim now less likely to generate warnings or exceptions
Run method now correctly calls self instead of self.model
Using SettlingCFSheet for LGN Sheets to re-enabled unopt tests for GCAL

Behaviour should be equivalent (to SettlingCFSheet_Opt) as the same
optimized joint_norm_fn is used and a mask of type NeighborhoodMask was
not needed.
Topographica script now warns and exits when using Python <2.7

The DICE tests on Topographic buildbot have been passing because
collections.OrderedDict was hacked into Python 2.6 on that system. In
general Topographica will not work on Python 2.6 and the DICE tests need
to use Python2.7.
UniformRandom pattern generator in measure_rfs supplied with name
Updated load_snapshot to work with topo.sim.model correctly
Replaced global View storage AttrDict with AttrTree
Added ProgressBar for measurements when not in the GUI
Added only_latest option to measurement StorageHook
Reenabled global measurement AttrTree in IPython Notebooks
Added buildbot status icons to README
Buildbot status now presented in a tabular format
Removed 'Buildbot Status' heading from table in README
Dimming for images
Merge recent commits