GitLab

* add metis.

* add test.

* construct partition id.

* link to METIS github repo.

* update metis.

* add a tool for partitioning a graph.

* update metis.

* update.

* update.

* fix metis.

* fix lint

* fix indent.

* another way of building metis.

* disable metis in windows.

* test windows

* fix.

* disable metis for windows properly.

* fix for tensorflow.

* skip test for gpu.

* make graph symmetric

* address comments.

* more comments.

* fix compile

* fix a bug.

* add test.

* change the default #hops of HALO nodes.
Co-authored-by: Ubuntu <ubuntu@ip-172-31-26-167.us-east-2.compute.internal>