[FEATURE] PSR-2 Compatible Method Names

[Bilal Gultekin]

Protocol Buffer Styling Guide suggests using camel case (with an initial capital) method names in service definitions. But when we do that, it's making the service file incompatible with PSR-2 (and PSR-12) because it generates the method names same as in the proto file.

Shouldn't the plugin generate PSR-2 (or maybe optional) compatible files no matter what is given? It looks like, that's how the java plugin works.

Thanks for the great tool BTW! It's very helpful.

[Anton Tsitou]

I'm open to that, but it will require patching the proto file compiler. We can conder something like that in future releases. Any PR will be appreciated.