2D convolution layer that uses GpuCorrMM directly, to get access to its extra features (i.e. padding)
Use Thenao version from Git; required for GpuCorrMM
Merge pull request #45 from dnouri/requirements-theano-from-git

Use Thenao version from Git; required for GpuCorrMM
First batch of unit tests for layers.
Merge pull request #47 from dnouri/test-layers

Add first bunch of tests for layer module
Allow all layers to be made bias-less by passing None for b