Mostly PEP8 in conv2d
conv2d tests
make_random_conv2D test
Use floatX for conv2d tests and add test for different numbers of input/output channels in conv2d
conv2d tests different error type for bad filters
Test for conv2d's lmul_T and lmul_sq_T methods
Fixed assertRaises syntax for Python 2.6
Fixed PEP8 formatting issue in conv2d_tests
Merge pull request #660 from bartvm/conv2d_tests

Conv2d tests