[FEATURE] Implement semantic versioning

[daks]

Is your feature request related to a problem?

This formula still provides ntp and ntp.ng states which is confusing and complicated.

Describe the solution you'd like

The solution to this problem is deprecate php legacy states and promote php.ng states to php ones, renaming them.
It means :

• implement semantic versioning as we do in other formulas with all tools to automate work
• create an initial release with current code
• create a BREAKING CHANGE version deprecating legacy states and promoting new ones

Describe alternatives you've considered

I don't see any other solutions.

Additional context