Update dependencies, but keep compatibility with Fastify 2.x (and Node.js 8 LTS)
Use 'check-runtime-env' latest release ('~0.3.0') with new features
Use Node.js assertions but in strict mode now
Ensure all works again
Feature: add new plugin option 'nodeStrictCheckAtStartup'
to check if JavaScript is in strict mode (by default true)
otherwise an exception will be raised at plugin startup
(safer option, to be sure to use modern code/settings)
Breaking Change: rename plugin option 'onNodeVersionMismatch'
into 'onCheckMismatch'; now this setting defines the behavior for checker
failures on 'nodeStrictCheckAtStartup' and 'nodeVersionCheckAtStartup' options