Add search feature to devtools panel

[MisterPhilip]

Depending on if/which front-end framework (#118) is used, we may need to add a custom search ability that overrides the default ctrl+f in the devtools panel (see: #87).

Ideally this would just open a search box at the bottom of the page, which (temporarily) filters out requests that do not match the search text.

[meatnordrink]

We would love to see this feature. We have a ton of analytics on our pages (not my choice), and filtering by analytics provider is awesome, but even so we often have quite a few events in the column for a page. Would definitely save time to be able to search for a given category name, for example.