Merge pull request #249 from dansbecker/master

Add mlp.PretrainedLayer
localdot-related docstrings
Merge branch 'master' of github.com:lisa-lab/pylearn2
removed incorrect usage of "refactor"
Merge pull request #251 from goodfeli/master

Doc
support for changing # of input groups
Merge branch 'master' of github.com:lisa-lab/pylearn2
start of fixed_var_descr support for sgd
more fixed_var_descr support
more fixed_var_descr support
Merge branch 'master' of github.com:lisa-lab/pylearn2
Merge pull request #252 from goodfeli/master

Support for changing # input groups
Merge branch 'master' of github.com:lisa-lab/pylearn2
correctly access on_load_batch
fixed wrong name of field access
Merge pull request #253 from goodfeli/master

make sgd support fixed_var_descr
Merge pull request #254 from dansbecker/master

Added input_space and output_space attributes to DeepComposedAutoencoder
started tuple_var
expose Dataset from pylearn2.datasets
make invert a general method of Preprocessor instead of just ZCA