Feature/many small fixes

Many small fixes, including

- removes unused JavaScript
- removes unused images
- fixes capitalization inconsistancies in vertical nav
- updates credits for icons and team members in humans.txt
- removes old test files from root
- updates wording in search box
- adds intro paragraph to search page that explains curated search
- adds link to Beckley
- adds filter to documentation page so that only those terms that are relavent to the site-wide documentation page display there. Other terms are used in tooltips only, but can still live in the documenation yml file. This is accomplished by using a `display` key term set to `false` if it should not display.
- adds chart notes to disbursement viz