The preallocated output size for make_vector should ALWAYS be the good
shape right now as it only depend on the ndim and that is constant in
the graph and we only give preallocated output of the same node.

This fix will be useful in the futur if we make other type of
preallocated output that could be of the wrong size.

[BUG] in fast compile related to inplace opt.

Add subgraph_grad

Bug and crash fix in fast_compile

This fix bugs on the CPU in fast_compile introduced in:
commit 4f8f0da5
Date:   Thu Feb 27 09:56:12 2014 -0500

Add tile in the doc.

Update the c_code_cache_version that was forgotten.

Mixed

Speed up matVecModM function.

Add consider_constant op

Use pip --user instead of --install-option

I don't know if there is a specific reason that --install-option='--prefix=~/.local' is used instead of pip's --user, but it seems to break things when installing Theano without root access (both myself and Jae Hyun had this issue).

Moved consider_constant from theano.tensor.extra_ops to theano.gradient, moved the optimization that removes it to theano.tensor.opt. Modified theano.compile.builders so it doesn't import theano.gradient, because theano.gradient now imports ViewOp from theano.compile and this would lead to a circular dependency.

Add new subtensor helper make_constant and use it to fix a bug in local_subtensor_merge.

Fix gpu crash and faster optimization

Add fast_compile tag so the optimization to remove the Op always runs. Use g_out.zeros_like instead of tensor.zeros_like so the op also works for sparse variables.