start refactoring bbb-webhooks to use a proper config library

bbb-webhooks/application.js

bbb-webhooks/callback_emitter.js

bbb-webhooks/config.js

bbb-webhooks/config/bbb-webhooks.logrotate

bbb-webhooks/config/custom-environment-variables.yml

bbb-webhooks/config/default.example.yml

bbb-webhooks/config/webhooks.nginx

bbb-webhooks/config_local.js.example

bbb-webhooks/extra/events.js

bbb-webhooks/hook.js

bbb-webhooks/id_mapping.js

bbb-webhooks/messageMapping.js

bbb-webhooks/package-lock.json

bbb-webhooks/package.json

bbb-webhooks/responses.js

bbb-webhooks/test/test.js

bbb-webhooks/userMapping.js

bbb-webhooks/utils.js

bbb-webhooks/web_hooks.js

bbb-webhooks/web_server.js