Fix master build on readthedocs

Useless sum in grad removed and test added

Added @regirster_canonizalize to local_reduce_broadcastable as the new fixes do not break the tests anymore

Add miniconda.sh to TRAVIS cache

The idea is to bypass the dependency on scipy that is in setup.py, by
- providing it explicitly in the requirement file, and
- explicitly installing theano, telling setup.py to ignore "install_requirements"

This is needed because the version of scipy on readthedocs is older than
the required one, but it is not an issue for building the doc itself.

Solve

Add dilated convolution explanation to convolution arithmetic tutorial

(empty line added)

added a blank sandbox/solve.py that just imports solve from slinalg and warns the user that sandbox.solve will soon be deprecated

added documentation for solve. I had to add it to doc/.../slinalg.txt as well otherwise the method signature looked ugly in sphinx

fixing subtensor.take

Trying to add miniconda.sh to
TRAVIS cache then avoir redownloading
of this resource for every build.

Need to be tested.

Small deprecation fix

Update TRAVIS config: tests splitted

Fix issue in local_subtensor_incsubtensor

This fixes an intermittent failure with non-default seed

Adding __props__ to all the Ops that has __init__

Grammar fix

theano/tensor tests splitted aroung theano/tensor/nnet