Merge pull request #281 from goodfeli/master

refactor of convolution code
disabled check that doesn't work with all axis formats
added test values to monitor inputs
fixed bug in BaseActs.make_thunk (thanks Fred)
added censor_non_alphanum
Removed pylearn.filetensor dependency for NORBSmall dataset.
(changed dataset to numpy format)
added dataset installation exceptions
Merge branch 'master' of github.com:lisa-lab/pylearn2
added scale argument to FoveatedNORB
fixed whitespace in retina.py
fixed crash bug in retina.py
moved EnvironmentVariableError to utils.exc
added show_examples script that works with NORB
DenseDesignMatrix.{restrict,convert_to_one_hot}
more standard options for norb
changed binocular viewer to cross eyed convention
formatting
weights view for retina
binocular weights report
fixed ImgActs gradient