Make it compatible with python 3

Grad argsort

Fix dnn_conv and dnn_pool docs

"each of" the top and bottom, left and right, etc.

Convert double recursion to simple recursion

Link d3viz doc in main tutorial

Fix GpuFromHost compilation error using libgpuarray

Scan fixes and speedup

Fix daily buildbot tests

Remove a few pieces of unnecessary code in the tests of sparse block dot.

When we copy a function, the new maker receive a graph that can contain inplace as this is the optimized graph.

Scan grad speedup bug

support for multiple axes in MaxAndArgMaxOp

Fix crash introduced by gh-3476

Scan backend speedup

Don't be more strict then numpy rtol on float64.

Multiple fixes preparing for multi-gpu

Fix arange to avoid overflow.