Selecting rows/columns to exclude from clustering analysis

[dtcarney741]

Some elements in a DSM are known as integrative. These generally have connections to many other elements in the system, and are placed at the top or bottom of the DSM. These will skew clustering algorithms if they're included. To prevent this, the user should be able to select elements to exclude from the clustering analysis functions.

This is very similar to the feature that was added to exclude elements from the propagation analysis.