use lodash.unionBy with lodash.isEqual to tidy up data manipulation

[Ron Waldon-Howe]

There are a few places in the YAML and JSON manipulation (in particular) where use of the following could result in simpler, tidier code:

• https://www.npmjs.com/package/lodash.isequal

• https://www.npmjs.com/package/lodash.unionby

[Ron Waldon-Howe]

Unfortunately, with this combination, lodash.isEqual only works on Objects and not Strings, so the result does not include any String values that it should. /shrug