Agent - 0.8.0

## [0.8.0] - November 18th, 2019 - Adds ability to limit the number of active api connections - Allows SDK keys to be bootstrapped during startup - Adds http server timeouts - Adds graceful shutdown hooks - Adds support for forced variation API - Adds support for experimentation APIs

https://github.com/optimizely/agent/releases/tag/v0.8.0