Added possibility to choose order for "defrosting" problems for contestant.

Implemented two approaches:

• By alphabetic order of problem name

• By increasing contestant last submit time for problem (thanks to snarknews for feedback)

Demo stand was updated

Distributive was updated

Hot Fix 1.9.1

• Fixed issue with wrong calculation of contestant last successful submit

Defrosting with presenter (experimental branch from master on GitHub)

Now you can use your presenter (for example, Logitech R700) for "defrosting" without standing behind your computer with S4RiS StanD! Enjoy the freedom!

• Next Step — button "Next" on presenter or Pade Down on keyboard

• Fast Next Step — button "Back" on presenter or Pade Up on keyboard

• Back step — temporary only by keyboard button "B".