Made a standalone executable to dump grid information for partitioning

[kjetilly]

Maybe this is already easily available, but I am not aware anything like this at least.

Currently only supports grid without wells. Does not support weights yet.

Use case: Running large cases of SPE11C, where the partitioning typically fails and consumes much memory.

Limitations at the moment:

• No well support
• No weights

The resulting output file can be partitioned with the gpmetis CLI program

gpmetis <file created> <number of procs>

For the manual

A new tool has been created to export graph data from the grid to allow for external partitoning.

Limitations at the moment:

• No well support
• No weights

Usage:

The output file can be paritioned with the command:

  $ gpmetis <outputfile> <num_partitions>

The resulting partitioning can be used with flow by specifying

   --external-partition=<outputfile>.part.<num_partitions>

Usage: dump_grid_for_partitioning <input deck file> <outputfile>