Binary operations: Support differing lshape-maps

[ben-bou]

Feature functionality
A clear and concise description of what the feature should do exactly and any alternative solutions.

Example:

a =  ht.ones(10, split=0)
b = ht.zeros(10, split=0)
c = a[ :-1 ] + b[ 1: ]

Globally, a[ :-1 ] and b[ 1: ] are compatible and the binop should compute. However, because they are differently distributed, it doesn't work. Because this cannot work without additional communication, maybe a warning should be given. A workaround I'm currently using is:

try:
  binop(op, arr1, arr2)
except:
  arr2.redistribute(arr1.lshape_map)
  result.larray = op(arr1.larray, arr2.larray)

(more details: https://github.com/ben-bou/heat/blob/redistribute/heat/core/_operations.py#L33 )

Additional context
Add any other context or screenshots about the feature request here.

This feature is important to ensure that scripts running with one process also run when using multiple processes.

[ben-bou]

Same for setitem if not already included