Add CAPTCHA support to OdysseySite

[zstumgoren]

Add support for reCaptcha to OdysseySite.

We know of at least two sites that do not require/allow registration and login, and instead require reCaptchaV2 to conduct searches:

• San Mateo #48
• Washington Oddysey portal

Implementation

Build on existing CAPTCHA work using anticaptcha

But try a less invasive decorator-based approach to detect and solve captchas, handle retries, etc.

• [x] Create decorator for Site class methods
• [x] Check config.yaml for captcha_service_api_key setting or raise error on captch-protected pages

[zstumgoren]

Basic implementation of reCaptcha_v2 support works for San Mateo and Washingston state Odyssey portal