* app's frontend and backend are combined and served together from Node.js

* add code block to demonstrate build process in a more readable way
  (other than the Makefile)
* emphasise the sensitivity of the JWT token

* NodeJS: v16
* NPM: v8
* Jest: v27
* Mongoose: v6

And fix some small issues along the way

* remove 'renders a todo add' test since it was a) the wrong place
  and b) already implemented by PR #36
* fix indentation and make sure that there is actually a user that
  the test tries to delete

* bump NPM from v6 to v7
* regenerated package lock files
* bump Node from v12 to v14

* removed hack folder and with it all code to install deps
* reworked `make build` to show more explicitly what needs to be done when
  producing an artifact
* bumped node version dep to v14 (to make jest work again)
* adjusted readme
* suppress console output when running jest client tests

* update server and client package dependencies due to CVE notifications
* update runtime dependencies
* add some information to various readmes (e.g. about the client being part of the bundle)

* glow is kinda distracting
* original test for title content prevents utilizing a change of
this characteristic form being used for demonstration purposed. The
additional test makes testing for the title more flexible and not
relying on its content

* adjust app readme
* revert change in server 'scripts'
* renamed 'stack' into 'hack' and split up Makefile into two to better separate
  devops scenarios from scoped deps management
* updated readme according to the make target changes

* fix file name typo
* remove logs in test do reduce noise
* prevent 'connection established' log in test mode to reduce noise
* rename test to make it more obvious that it does not require (or create)
  a user object

* update mongoose, jest and nodemon to address security alerts triggered
  by dependabot
* 'test' target had a bug introduced by using wrong syntax
* renamed server scripts to clarify the distinction between invocations
  in local development, CI and actual operations

ESLint is only part of the application frontend and only invoked implicitly during build time

* adjust mongoose configuration
* documents more make targets in readme
* applied npm scripts convention of the client to the corresponding
  server scripts in order to be more consistent (`start` is now meant
  for local development)

* keep both in gitignore, since the default still exist

* tech stack can be installed locally and will be used by app-related
  targets if available
* bumped minimal required npm version to 6.14 for server and client

* readme files for the repository and the app
* makefile ans the main entry and documentation
* remove create-react-app from client code

* change behaviour so that service still comes up regardless whether db connection
  can be established or not (see 12-Factor-App) - loosely tight to backing service
* instead, it will log to stderr hinting this issue
* successful port binding is still required

* introduce a test on the server to see if user creation works (backend process <-> db only;
  still needs a test that involves the router, too)
* main server process is no connection-aware and wont start if database is not reachable
* some renaming, cause it's more descriptive
* unify quote usage