Create new "form" example

[tomastrajan]

The starter project contains lazy loaded examples module which currently contains following examples:

• todos
• stock market
• theming
• auth only route

Create new example demonstrating "real life" complex reactive form using a form builder.

• should live in examples/form route
• should have dedicated component, reducer (effects if needed)

Form should have following features:

• record to be edited (eg user record with edit, save, reset button)
• use various input types (eg input, dropdown, slider, toggle)
• use unified "real life" like content (eg pizza creator, user editor, order creation or similar)
• use form validation with validation messages (eg required, email, more than ...)
• reset button ( to clear form to original state )
  ...

Please feel free to suggest, enhance or improve anything!

Feel free to check out Contributors Guide for useful tips and hints that help you get started.

[timdeschryver]

Closed via #317.