Automatic duckpan app restart on IA update

**Which issues (if any) does this change solve? (please link them here)**
https://github.com/duckduckgo/p5-app-duckpan/issues/52

**Briefly describe your fix. Are there any important details we should know about?**
Alternate strategy to https://github.com/duckduckgo/p5-app-duckpan/pull/175 code reloading.  Adds the role App::DuckPAN::Restart which _restarts_ the running duckpan application automatically when instant answer code is changed.

Incorporates https://github.com/duckduckgo/p5-app-duckpan/pull/190 as well since the current query console does not exit cleanly when killed.