Improve validation

[BalaM314]

The current validator just checks for valid JSON syntax, but there are still a lot of possible errors it doesn't catch

• invalid type (missing address, missing name, misspelled address, misspelled name)
• invalid value (something other than a string)
• typo in value (invalid ip address)

I can write a json validator to catch more errors and run it under github actions

[Anuken]

A potential idea for the validator:

• Grab the addresses from the diff
• Parse the JSON
  • Return an error if this fails
• Ping each server
• Return ping results, post them as a message on the PR

In addition, it would be nice to have a Github bot that automatically pings the servers when requested, using this same mechanism.

Some servers probably block Github Actions pings, but that's better than nothing.

[TheRadioactiveBanana]

A potential idea for the validator:

* Grab the addresses from the diff

* Parse the JSON
  
  * Return an error if this fails

* Ping each server

* Return ping results, post them as a message on the PR

In addition, it would be nice to have a Github bot that automatically pings the servers when requested, using this same mechanism.

Some servers probably block Github Actions pings, but that's better than nothing.

I might actually code that, it is a good idea