Taking into account the case when MLP is a layer for another class.
Changing monitoring interfaces for nested MLP.
Including an example.
Deleted debugging lines and nesting more.
Merge branch 'master' of github.com:lisa-lab/pylearn2 into mlp_part_of
Addition of the L1 penalty.
Addition of a MLP Layer not being the last layer.
Correction of get_monitoring_channels_from_state
Correction for monitoring and input_space checking.
Addition of checkpoints for input_space presence.
Updated the docstring for MLP.
Update docstring. Sharing of rng and batch_size.
self.mlp is the direct parent.
Merge branch 'master' of github.com:lisa-lab/pylearn2 into mlp_part_of

Conflicts:
	pylearn2/models/mlp.py
Merge branch 'master' of github.com:lisa-lab/pylearn2 into mlp_part_of
Line breaking fixes.
Break lines fixes.
Merge branch 'master' of github.com:lisa-lab/pylearn2 into mlp_part_of
fixes #266 Adding input validation to yaml config parser
Fixes #266 and #267 which checks yaml input for duplicate keywords
Added a get_layer_monitoring_channels method.
Deprecated the others.
Syntax errors correction and line breaking.