fix tests/unittests/supervised/knn/lsh/test_nearoptimal.py float equality
fix tests/unittests/datasets/test_datasets_datasets.py addField
add BackpropTrainer parameter for trainingset and validationset
change local vars trainingError and validationError to attributes
add raised exception on NaN in backprop.py
minimal refactoring in backprop.py
created unittests/supervised/trainers/test_backprop.py for bug demonstration
fix test_backprop.py
add threshold for convergence check in backprop.py
fix variable name in dataset.py
Merge branch 'master' of https://github.com/abbgrade/pybrain

Conflicts:
	pybrain/tests/unittests/datasets/test_datasets_datasets.py
	pybrain/tests/unittests/supervised/knn/lsh/test_nearoptimal.py