Fix a pyflakes complaint.
Add kernel stride support, rename subsample.
fix image viewer

replaced os.popen by subprocess.Popen; platform specific commands
cleaned up imports
moved check_cuda to cuda convnet and made its error message customizable
for features other than maxout
factored out some of the initialization from maxout so it's useful for
other convolutional layers
fixed some bugs in the refactor
Merge pull request #279 from bbudescu/img_view_subprocess

fix image viewer
pep8
conv c01b transpose
ImageActs gradient
Merge branch 'master' of github.com:lisa-lab/pylearn2
Merge pull request #271 from dwf/maxout_stride

Strides for maxout convolutional models
named arguments to avoid them going to stride
Merge branch 'master' of github.com:lisa-lab/pylearn2

Conflicts:
	pylearn2/linear/conv2d_c01b.py
	pylearn2/models/maxout.py
Make maxout test work when device=cpu when cuda is available.
Patch old pickle files that don't have kernel_stride.
more support for strides
repaired botched merge
support for not passing output_shape if stride=1