Create kcomponents_weighted_graph.py

[kasturi2903]

This algorithm allows to identifying kcomponents of directed graph.

Related discussion: #7106

[rossbar]

Before getting into the details, there are some high-level organizational things that need to be taken care of before this can be considered.

The big one is the test failures, which are due to duplicate function names in the namespace. The first thing to decide from this perspective is how this functionality would be exposed to the user. I would expect the most straight-forward approach would be to add a weight kwarg to the existing k_components function. Either way, defining a new function with the same name is a non-starter.

The second important piece before this can really be reviewed is to add tests for the new behavior.

[rossbar]

See also #1618 which is related - at the very least, the API changes in #1618 are more in line with what I'd advocate for in introducing this feature to the user (i.e. kwarg switch rather than adding/renaming functions)