Added new option methodNamingConvention to abstract php class

[web-mi]

This PR added new additionalProperty "methodNamingConvention" to handle special cases with mutiple properties like "test" and "_test" which will end in the same getter and setter "getTest". (e.g. Rocket.chat GetApiV1ImList200ResponseImsInner.php)
By setting methodNamingConvenetion to snake_case the method names will be snake_case like "get__test" and "get_test" which is not the php default but solves the problem and makes the generated classes useable without a duplication error.
Also if there are two properties in openapi.yaml like "o_auth_test" and "oauth_test" it will end in a duplicate getter like "getOAuthTest" and "getOauthTest". (e.g. Keycloak RealmRepresentation.php)

This will add a solution for #1633
Its an alternative for #1634 too.

Technical Commitee PHP:
@jebentier, @dkarlovi, @mandrean, @jfastnacht, @ybelenko, @renepardon

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[naetraga]

i like it. @web-mi great job 👍

[wing328]

This PR added new additionalProperty "methodNamingConvention" to handle special cases with mutiple properties like "test" and "_test" which will end in the same getter and setter "getTest"

thanks for the PR

have you tried the operationId mapping option? Would that meet your requirement?

ref: https://github.com/openapitools/openapi-generator/blob/master/docs/customization.md#name-mapping

(this is not to say we won't accept this PR. it's still a good idea to have the option)

[web-mi]

Yes i already have seen that option. But i'm automatically generating multiple api clients directly from their resources and i don't wan't to fix it all the time if they change something. :-)
With the snake_case functions i had to fix nothing so i thought it would be a good idea to switch to the snake_case functions. ;-)

[wing328]

2 suggestions:

1. merge the latest master to this branch to fix the build errors

2. instead of adding a new option, copy the modelPropertyNaming option from some other generators which already support such use case to customize the property naming, e.g.

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java#L52

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java#L171

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java#L223

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java#L262

https://github.com/OpenAPITools/openapi-generator/blob/master/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java#L298

let me know if you need help