Add missing arguments to GpuKernel_init

Mixed

Windows fixed and support Anaconda blas on Windows

Add numpy.compress to theano.tensor

Elemwise tester uint poc

Tracking Ops with grad methods returning None

Fix travis

Pep8

Reduce the number of allocation/reuse allocation of ndarray #1943

Remove consecutive functional inverses to optimize

In fast compile mode, non-inverse functions can be split into two
operations, which broke one of the asserts.
Also added exhaustive tests for all inverse function pairs.
Abstracted out the test assertions to enhance readability.

See:
https://github.com/Theano/Theano/issues/864

Correctly disable g++ on windows when it isn't available. This cause sometimes an import error related to gof. Othertime compilation errors.