* Fetches 'category' for the current URL when popup is first loaded.
* Customizable styles have "Customize" button next to "Install"
* "Customize" button opens a new tab to the style page.
* Removed all console.log() statements (except when `catch()`ing errors).
* "Find more styles for this site" renamed to "Search on userstyles.org".
* Only appears below search results after "Find more styles" is clicked.
* When style is installed from serach results, it no longer appears in the results.
* "Install" uses already-fetched .JSON data. Avoiding useless call to download().
Fetches .json for each search result and asserts style applies to the page.
Still needs:
* Smarter search ("metacritic.com" = 0 results)
* Faster (or parallel) fetching of search result .json files
* Better feedback ("loading" messages)
* Detection of styles that can be Customized
* Install styles using searchResult.json (not downloading)