add comparison of labeling tools to repo

[kgarwoodsdzwa]

for now, create a folder in parent directory and inside, add the document containing the comparison of different labeling tools. As we build out more data exporters, could make sense to link the comparison to the usage of the exporter tools. But for now just to exist in the repo is good. Branch off dev with the issue num at the beginning of the branch name.

[valerieporter]

I created a new branch, "116_software_evaluation", and added my software_evaluation.md document to a new folder: documentation/labeling_software.

[valerieporter]

We may want to discuss turning this into an excel sheet rather than keep as a document.