Add more timing options

[Artemis21]

Possibilities:

• Max time for stage.
• Reset time at start of stage.
• Byo-yomi (Players are given "parcels of time" - when other time runs out, they open a parcel, when that runs out, they open another. Crucially, once a parcel is opened, it cannot be used on a subsequent turn, even if not fully used up.)
• Bronstein Delay (time increment is never more than time taken for move)
• Hourglass (while one player's time decreases, their opponent's increases)

Conscious of issues with providing too many options...

[Artemis21]

• Add increment to the first move (FIDE/US Chess)