small doc update following email from John Salvatier.

I merge it myself as this is a trivial doc change.

fix gh-363 Move optimization from basic.py to opt.py.

note about pep8 check in emacs

Small

Delete local var not used anymore and use the right variable instead of ...

Vm allow gc of all intermediate results at the end of function call.

Only the lazy op cause intermediate result to don't be gc during compilation.

Small

The Updates object now check that the key are SharedVariable when we pass them in the __init__ function.

Add script to test PR.

those come from ipython that have the same license as Theano.

Doc

fix hg-538

fix context problem with pycuda by checking it is imported before.

Opt

We already checked that the node is still in the env before we process it.