v0.16-google-palm2

What's Changed

• decouple mongo element with domain element by @iceljc in #160
• Add timer to ITokenStatistics and update docs by @hchen2020 in #161
• Fix PizzaBot build issue. by @Deep-Blue-2013 in #162
• Add RoutingContext to manage redirection stack automatically. by @hchen2020 in #163
• Allow retry 3 times for format response in Routing. by @hchen2020 in #166

Full Changelog: v0.15-routing-handler...v0.16-google-palm2