"theano-cache basecompiledir purge" is useful when the kernel or Python
version changes, as cache directories accumulate.

Always put arch bitwidth in cache

Multiple mode

Also move local_bitwidth to gof/compiledir, import it directly in
theano.gof, and use the latter path.

This is to avoid loading modules compiled with one architecture from a
Python with a different one.

mrg multinational grad

Fix march on windows

Travis ci scipy

don't use the equivalent flags for -march=native for llvm 

This remove a warning introduced in gh-1265.

Change an assert to a warning and disable the functionality.

This was breaking Theano on briaree

I also changed the parsing to make it work with g++ 4.4.4 4.5.1 4.6.3

add equivalent of -march=native to g++ command line.

Sparse

This speed up the test time of the other part.

This allow to remove the value itself from the graph earlier.

crash fix: theano.sparse.Dot didn't created the output var with the right number of dimensions when one input was a vector.