Fix JSdocs in new components

[robyngit]

Noticed a few minor with the jsdoc comments in the new 2.28.0 models, views, and collections. This issue is to track fixing those for the next release.

• @classdes --> @classdesc - doesn't break the jsdoc build, but description doesn't show up on the docs site
• add missing @lends classname.prototype - without this, the method documentation doesn't show up in the class documentation on the docs site
• add missing @extends Backbone.Model, or which ever class it extends

For example, see the ViewfinderModel docs. Even though this class has a description and documented methods, they don't show up on the docs site because of the missing @lends tag and the typo in the @classdes tag.

MetacatUI is missing JSdocs in many of the older components as well, but this issue is just to fix the new components so that we can continue the practice of adding complete documentation for new or modified components going forward.