Return a struct from gin's RegisterHandlers instead of an interface - #555

I included autogeneration of new examples via go generate directives in the gin example folder that were missing which is likely what lead to this breaking change being merged without notice. If the changes make the generated code change in a breaking way, it will fail in make test now when it tries to build the example packages. make test runs after make generate so we should catch breaking changes this way.

Hi! Sorry to nudge you like this, but could you provide any estimate on when this is going to be merged? #485 poses major discrepancy when using this generator. I can see a solution had already been implemented in the past, but got reverted later due to inconsistencies with usage examples. If that's the only issue, would it be much of a trouble for you to align the documentation to match the actual API?

Afaik this project had some breaking changes in the release a week or two ago, perhaps now it's a good time to carry this change out.

Thank you for submitting this PR, @jazware — but we need to close it. Goal (1) — accepting gin.IRouter instead of *gin.Engine — was fully achieved by #879 (commit e8dc342d). Goal (2) — returning a concrete *gin.RouterGroup instead of *gin.Engine — was resolved differently: the maintainers ultimately chose to make RegisterHandlers void, a different design decision. So while the input-type concern is fixed, the return-type direction wasn't taken.

Apologies for the long wait, and thanks for the contribution.