Random generated decks mode - match and tourney (aka random Gauntlet)

There are can be random deck mode for matches and tourneys -- decks will be random generated for each player before match/tourney begin.

It's like "gauntlet tourney mode" (#1577) but uses random decks. And it's can use same mechanic:
* game owner open game create dialog, select game modes and fill decks list;
* decks can be added manually (gauntlet mode) or generated by standard dialog (random mode);
* min decks amount must be 1;
* before match\tourney start -- server select random deck and assign it to players (on tourney it's a same deck for all matches);
* one deck for one player (when decks ends then server can choose from the full list again);

Start by reviewing the existing gauntlet tournament design in issue #1577, then trace the game creation dialog and the server-side match and tournament startup flow. Done means supporting random deck generation, a minimum deck list of one, random assignment before play, tournament-wide deck consistency, and reuse when the list is exhausted.

Written by the indexing model from the issue text.