Better naming control

[stojsavljevic]

I want to have more control over naming logic for Java parameters and method names.
Currently, there is a logic that takes displayName attribute (#177) but that might not be sufficient.
Instead I want to introduce a config option for naming logic based on either on displayName, some custom annotation or plugin default logic.

New configuration option will be logicForParamsAndMethodsNaming and it will accept following values:

• DEFAULT
• DISPLAY_NAME - for considering displayName attribute when available. It will be cleaned for Java conventions.
• ANNOTATION - for considering custom annotation called javaName on method definition. It will be taken as is.

This logic will apply when generating names for:

• headers
• queryParameters
• uriParameters
• method names