Type property for long data type is invalid and incompatible with swagger spec generated from proto3 sources

[evanmcclure]

The type property of the long data type is invalid. In the spec, long requires type=integer, but the proto3 swagger spec generator produces type=string.

References:
https://github.com/OAI/OpenAPI-Specification/blob/master/versions/2.0.md#data-types
https://developers.google.com/protocol-buffers/docs/proto3#json

Proposed solution:
Change the spec to accept type=string.

[handrews]

If this is still a concern, it needs to be raised with the Swagger generator tool.