Add a web surfer agent that can search and browse the web. (#1093)

* Initial commit of WebSurfer. Adds the browser_utils, and related tests. WebSurfer will be added in a subsequent commit.

* Added the web surfer agent, and related tests.

* Added a notebook to show how WebSurferAgent works.

* Fixed a typo.

* Updated test_web_surfer for compatibility with #1110.

* Updated skip_oai logic.

* Fixed code formatting.

* More pre-commit fixes.

* Added block to contrib-openai.yml

* Added block to contrib-openai.yml

* Added hook for BING_API_KEY

* Temporarily commented out other tests, per request.

* Fixed indentation (maybe?)

* Restoring contrib-openai.yml