added code and tests for adadelta
added adadelta
FIX: bound was not respected
aesthetical
patience now looks at the `n_iter` field of an info dictionary
added flask theme for docs
option for sparsify_columns to keep the diagonal
fixed test for patience
added tests for minibatches
Merge branch 'master' into feature-adadelta
GradientDescent can now be restored from saved info dict.
`n_iter` now initialised in base class
rmsprop can now be discontinued
refactorings
accidentally created in the wrong position
rprop serializable
disable serialization tool funcs for bfgs (raises exception)
made non-erializability explicit
Merge branch 'master' into feature-adadelta
added state fulness to adadelta