Improving TypeScript definitions

Improving TypeScript definitions related to routes registration.

Issue ref: #79

Adding routes method

Added:

• Re-adding routes() method to expose registered first level routes.

  Expected format:

  [
     "GET/person/:id",
     "DELETE/person/:id",
     "GET/health"
  ]

Issue ref: #77

Increase compatibility with Node.js http.Server.listen method

Added:

• Fully support all http.Server.listen method arguments on restana.start method.
• AWS SAM serverless example application is now referenced in readme.

Update TypeScript definitions

Adding req.body types definitions.

Enable strict mode

Adding 'use strict' to all .js files.

Update dependencies

• Updates dependencies.
• Removes package-lock.json from module level.

Improve TypeScript support

Adding typings for nested routers registration API.
Thanks to @kelvinfloresta for his contribution here.

Update dependencies

Update 0http to v2.2.2

Improve documentation

Adding the following topics to readme:

• Nested Routers
• Cloud Functions for Firebase integration (thanks to @adrianjost)

Bump 0http to latest version

Update dependencies.