Use logger instead of printing. Update error message.

We where casting a 64 bit ptr to 32 bit.

This was done with much help from Aaron Defazio. fix gh-1547

The Attribute Error is catched in cmodule_key

Fix command not returning with recent mingw64

Fix infinite loop when we can't create the lock_dir directory.

Add test for mixed int/scalar variable in "size" arg of mrg samples

better error message

Fix bug with mixed types in shape of random sample

This fixes a bug when the shape is a tuple containing both symbolic
and numeric scalars.

Better error handling and buildbot

Do not return None in scalar op's grad, add tests

Fix cycle

Add case where 'axis' is a numpy scalar array

The python error is already set by device_malloc and it contain more information.

If the 'axis' variable is a numpy scalar array (like numpy.array(1)), these conditional branches will fail as it tries to build a set over the non-iterable array. I've added another branch to handle this case.