Consider specialized DimShuffle C-implementation

[ricardoV94]

Description

Right now DimShuffle uses an external C-op that is generic over variations of DimShuffle. In the older time it used to be one of the regular unreadable inplice c_code methods, which used the input/output ndim information directly, and could just define shape/strides as a constant size array and allocate it without a loop, like we have now.

This is probably a minor optimization, may not even buy us anything. This issue is a low-priority thing to just keep in mind.