added decorator middleware (only with to_camel func)
done with camel_snake converter
moved middlewares to app/middlewares, and moved tests
renamed: middlewares => middleware, fixed tests
added mocked tests for middleware
renamed middleware tests
refactored spec
renamed: middleware/decorator => /camel_snake_exchanger
Merge branch 'master' into middleware
fix sinatra-reloader, change modular app style
Merge pull request #32 from junsumida/middleware

[Check Please] Middleware to convert camelCase and snake_case