[Erlang] Enhancements to Erlang server generator

[wing328]

Description

• Write specs for static exported fuctions
• Write specs for generated exported fuctions
• Add datetime/date validation
• Separate gigantic api to submodules and refactor the routing
• Add tests for the validators
• Add integrational test for the whole cycle
• Add validations of definitions with inheritance
• Add proper response validation (this list hack is so weird)
• Fix enum validation. It doesn't work correctly when the parans is in qs/header

Swagger-codegen version

Latest master (Sep 2016)

If anyone wants to work on any of these tasks for erlang-server, please reply to let us know.

Ref: #3758

cc @galaxie

[hachreak]

Hi at all,
if someone is interested, I made a erlang module to load the swagger file and build the cowboy routing configuration. :)
https://github.com/hachreak/swagger_routerl