Gem speedup

Some timers in the game can be sped up by spending gems. These are:
- the remaining time of firestone researches
- the remaining time of missions
- the remaining time of experiments
- the remaining time to map reset when all missions are finished (if unlocked)
The gem cost varies depending on how much time is left on the timer:
- 0 – 3 minutes left: free
- 3 – 60 minutes left: gem cost = (seconds remaining / 3600) * 100
- 60+ minutes left: gem cost = (seconds remaining / 3600)0.6 * 100
When you click a speed up button, a confirmation window pops up. If you then confirm the purchase, the amount of gems shown is deducted and the timer is set to zero. For a free speedup (gem cost 0), no confirmation window is shown.