Json-server-py

* Improve rewriter [431](https://github.com/typicode/json-server/issues/431)
* Improve watch mode [427](https://github.com/typicode/json-server/pull/427)

* Fix [396](https://github.com/typicode/json-server/issues/396) PUT/PATCH saves the updated item with an id that has been converted to string

* Fix [221](https://github.com/typicode/json-server/issues/221) `nohup` support
* Fix [420](https://github.com/typicode/json-server/issues/420) TypeError when watching `db.json`

* Fix
* [412](https://github.com/typicode/json-server/issues/412)
* [451](https://github.com/typicode/json-server/issues/411)

* Shorter `uuid`
* No automatic conversion of strings to boolean or integer
* Create a default `db.json` file if it doesn't exist
* Fix
* [361](https://github.com/typicode/json-server/issues/361)
* [363](https://github.com/typicode/json-server/issues/363) [#365](https://github.com/typicode/json-server/issues/365)
* [374](https://github.com/typicode/json-server/issues/374)
* [383](https://github.com/typicode/json-server/issues/383)
* Updated dependencies and codebase to ES6

* Fix `Links` header