Change "Naming Strategy" to "Naming Convention"

[JFCote]

Very important to stay backward compatible for a while. Maybe add a warning log when people use the old one and say it will be deleted in a future version.

[jmini]

With the same move, I suggest to rename appelation to designation:

openapi-style-validator/lib/src/main/java/org/openapitools/openapistylevalidator/ValidatorParameters.java

Lines 10 to 18 in c96cc48

	private final String appelation;
	NamingStrategy(String appelation) {
	this.appelation = appelation;
	}
	public String getAppelation() {
	return appelation;
	}

Of course only in the new enum NamingConvention.

[JFCote]

@jmini That make sense