Document purpose of `installWMA.sh` script

[jhlegarreta]

The purpose of the script https://github.com/SlicerDMRI/whitematteranalysis/blob/6d93b6452b32ebedbee29674766abfe752dd1d04/slicer/installWMA.sh

is not documented anywhere. Is it useful/relevant so that WMA can effectively call Slicer modules?

Also, it contains hard-coded

• The INSTALLFOLDER is certainly a hard-coded macOS path; if the script is relevant, can this be made flexible enough to be used at least for a Linux OS?
• If the parent folder says slicer, there are no Slicer paths present in this script.
• The WMAFOLDER can be an arbitrary, so not sure how Slicer can be aware of this path.

Happy to help/test.

[ljod]

I don't remember the history of this, but if it is unused I recommend removal