Adds boat generator
Merge branch 'master' of https://github.com/tdeekens/tda452-code

* 'master' of https://github.com/tdeekens/tda452-code:
  Adds support for placing ships and flipping them.
  Adds boattypes as data-attrs.
  Adds control sidebar and flip btn.
  Changes boat coloring on field.
  Adds legend to field and styles 80s.