Merge pull request #1561 from lamblin/fix_mpi_python3

Update MPI test to work with python3
Merge pull request #1556 from nouiz/mixed2

Faster compilation and sparse stuff.
Don't override the NumPy error message.

Otherwise, we don't know if the problem is missing memory or not.
Assert that curand output dtype is float32.
Merge pull request #1562 from nouiz/err_msg

Don't override the NumPy error message.
Split back the arguments from multiple-arg options
Accept options specified more than 2 arguments

like -option val1 val2
Merge pull request #1560 from lamblin/fix_new_llvm

Fix -march detection on newer llvm
Added second derivative to max downsampling function
Only try to find duplicates in non-sequences.

This should fix a bug in Pylearn2 when using scan to perform linesearch.
allow one of the eval points to be None
dont check value for None eval point
new test
fix typo
Merge pull request #1568 from pascanur/fix_Rop_dot

Fix rop dot
Merge pull request #1566 from lamblin/fix_scan_linesearch

[WIP] Fix bug in remove_constants_and_unused_inputs_scan
Print the flops with the memory profiler.
Added a note about python2/3 in the ubuntu installation instruction.
Use only one pass over the toposort for some blas inplace opt.
Remove the old hack for flops computation now as it collide with the new one. They reuse the flops attribute.