* Standardized values in the example configuration
Removed what appear to be an actual API key from the example configuration.yaml block. And, replaced with values as described in the [developer docs](https://developers.home-assistant.io/docs/en/documentation_standards.html#component-and-platform-pages)
* Standardize example configuration-ecobee
* Standardize example configuration-coinbase
* Standardize example configuration-google assistant
* Standardize example configuration-cloudflare
* Standardize example configuration-cloudflare
* Standardize example configuration-habitica
* Standardize example configuration-ifttt
* Standardize example configuration-openalpr
* Standardize example configuration-multiple
* Standardize example configuration-instapush
* Standardize example configuration-llamalab
* Standardize example configuration-notify
* Standardize example configuration-mailgun
* Standardize example configuration-MULTIPLE
* Standardize example configuration-rtm
* Standardize example configuration-spotcrime
* Standardize example configuration-trafikverket
* Standardize example configuration-uk transport
* Standardize example configuration-wunderground
* Standardize example configuration-wsdot
* Standardize example configuration-telegram
* Standardize example configuration-tts
* Standardize example configuration-tts, vultr
* Replace email entry
* Replace IP address
* Place email address
Fix inconsistency where "domain" is required but "sandbox" can also be used to specify the domain. It appears that the package https://github.com/pschmitt/pymailgunner in def guess_domain allows multiple domains and "sandbox" can be used to choose a sandbox domain over a normal domain. As far as I can tell, this feature isn't used by the Mailgun component. There are also updates to the Mailgun Notify doc.
