Add new multicol protocol

[vshekar]

This is a new implementation of multicol. Previously, the user would select the number of centers that would be collected on without knowing where the centers would be. It also used to be its own collection type

Now multicol is simply standard collections that you would add to any raster. The user will select an already existing raster and then click on the "Add Multicol Centers" button. This will open a dialog that will display the heatmap, where the user can manually select centers or use the automated algorithm.
Once selected, clicking the "Submit Centers" button will add standard collections to the queue with the raster as the parent