This drops fomantic-ui as css toolkit and introduces tailwindcss. With
tailwind there are no predefined components, but it's very easy to
create those. So customizing the look&feel is much simpler, most of
the time no additional css is needed.
This requires a complete rewrite of the markup + styles. Luckily all
logic can be kept as is. The now old ui is not removed, it is still
available by using a request header `Docspell-Ui` with a value of `1`
for the old ui and `2` for the new ui.
Another addition is "dev mode", where docspell serves assets with a
no-cache header, to disable browser caching. This makes developing a
lot easier.
For some to me unknown reason, changing the dom slightly (removing
hidden elements), resulted in a different event dispatching. The cards
while being attached to an event would reload the page as if the event
is propagated. This happned by commit #8d7b3c7d in Home/View.elm.
Adding the hidden nodes back into the dom, "fixed" it.
This change now gives a better fix in assuring that every anchor has
either a sensible `href` or an event and a `href #`.
