SetSubtensor.

1) Fixed __eq__ to work when other is not of same type as self.
2) Optimized TensorConstantSignature to compare data.sum() before comparing all elements.

different ids that compare equal.

[recursive] handling of code versioning for ops like Elemwise, CAReduce, etc.

Changed the default cache version of Op to ().

Added c_code_cache_version() functions to many Ops that were using the default
before.

scalar/basic.  There is also a cast function, which is used in the grad() of ops
that might upcast their arguments, to downcast the corresponding gradients.

types.

the deprecation warning on startup.

problem.