as a docstring

supports C code

bug fix

NotImplemented

Minor stuff

It was setting the root logger level to DEBUG.
Also, I do not think the level of the scan logger should be DEBUG
anyway, it should be WARNING by default.

Documentation improvements

Consistent & correct handling of integers and gradients

-Documentation and implementation of a consistent way of handling gradients and integers
-Type checks that ensure the gradient is always floating point and not an integer
-Type checks that ensure the gradient of an integer is always undefined or 0
-An upgraded version of connection_pattern that provides theano with enough information to answer questions like "is variable x a function of variable y?" accurately