Fix in local_dot22_to_dot22scalar

Fix the tutorial to make it work with python 32 and 64 bit.

Add tests and opt one more case.

new op wasn't added there.

Fix compilation crash reported in gh-1518 for gpujoin.

Update message to mention the need to clear the cache

BUGFIX: tutorial -> Derivatives in Theano -> Jacobian times a Vector -> L-operator.

Add init_code mechanism to register code in module init function

Always call hashlib.md5 on a C-contiguous array

Scan crash fix

Use half_nbits floats instead of nbits. fixes gh-1510

Use compat.python2x.all instead of numpy.all on generator

instead of asserting they did not exist.

Sparse updates

Otherwise, the generator evaluates to "True", because numpy.all does not
actually iterate through it.

Also add test case to check that m[0, idx_list] triggers full
advanced indexing, not "take".