Similar lists were added recently in elemwise.py: it is better to re-use
existing ones.

Update internal doc for release

Minor stuff

Comparing strings with 'is' is dangerous, as there is no guarantee that
Python will store similar strings into the same memory space.

In filter, raise TypeError or ValueError.

type.is_valid_value relies on filter() raising either TypeError
or ValueError for invalid values, not AssertionError.

Sparse indexing

Optimization to move tensordot to GPU

For instance, m[:,a:b], or m[a:,:b]

Some types (like Generic) allow for a value of None.
We should not consider it an error.

updated Assert docstring as Fred suggested

Fix misc buildbot tests

Some doc

Error was:
ImportError: No module named theano