This is the first implementation of a theme manager. It’s a rebased and
revisited version of #792.

Related to #808

When closing the app/game tab with a zone revealed the client will
crash. This was due to the zones not being deleted.

+ Removed unused buttons
+ remade button art
+ fixed crash with font colors/replays
+ removed unused timestamp label in replay

Before:

After:

Add a configuration toggle to enable alerts when spectating.

Default behavior is to not alert.

Games with only 1 player will now not focus on the chat when starting
the game. This helps with goldfishing.

+ Added room name
+ takes you to kicked game tab

Two regressions; depends on the fix for #684, too

Its easy to not see that you have been kicked right now. This makes it
more apparent.

When the game starts the line edit now has focus immediately.

Running cockatrice in valgrind i didn't found any bad memory leak
(good!), but only a few jumps depending on uninitialized variables.
Even if the possibility of crashes are remote, it's nice to sort them
out.

Ref #142

This is @mcallahan's patch — see #35. I had to apply this diff by hand,
because both `git` and `patch` refused to apply it and I didn't know
how to resolve that. Consequently, there might be an error.

QPainter.drawRect()

deck editor is tab, replay viewer is tab, deck editor shown by default, cache window geometry between sessions, 'open this deck in deck editor' open in game

context menu for a message sender's name in chat; also display the user level icon next to the name; minor consistency and type-safety changes

improved token dialog w/ storage inside the deck list - now we need a reliable online source for token data (preferably with pictures)