Help tree-shake lodash

[ornic]

Now webpack packs full lodash with react-diff-view. There is a way to reduce bundle size:

https://www.azavea.com/blog/2019/03/07/lessons-on-tree-shaking-lodash/

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.