[C# .NET 2.0] 'Event' & 'Response' words crush code-gen

[aleksei-saharov]

Hi, all

I found that code generation to C# .NET 2.0 do not work if I use 'Event' or 'Response' word.

YAML

swagger: '2.0'

info:
  version: "1.0.0"
  title: <>
    
paths:
  /ping:
    get:
      parameters: []
      responses:
        '200':
          description: Success
          schema:
            $ref: '#/definitions/Response'
        '404':
          description: Success
          schema:
            $ref: '#/definitions/Event'
          
definitions:
  Event:
    type: object
    properties:
      Message:
        type: string
  Response:
    type: object
    properties:
      Code:
        type: integer
      Message:
        type: string

I got Code Generator Error. I did not have it with C# (not C# .NET 2.0) client generation.

I think that there are reserved words for generator but they did not flag as reserved.

[wing328]

@aleksei-saharov fixed via #4620. Please pull the latest master to give it a try.