* Add a new Pushover provider (#129)
- Adds new provider named Pushover with corresponding tests
- Adds Pushover as a provider to the configuration and adjusts test accordingly
- Adds Pushover to alerting_test.go, provider.go and type.go
- Updates the readme with configuration details
* Correct import order
* Fix some missing pushover references
* Apply suggestions from code review
* Rename application-key to application-token for Pushover
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Co-authored-by: TwiN <twin@linux.com>
Closes#308
Work remaining:
- Add the documentation on the README.md
- Test it with an actual Ntfy instance (I've only used https://ntfy.sh/docs/examples/#gatus as a reference; I haven't actually tested it yet)
