Increase cost of DOME from 1600 to 1800

Just move this slightly later, and make DOME-first rushes a bit more
risky.
Merge pull request #4810 from chrisforbes/delay-dome-balance

Adjust RA balance
Add changelog entry for Radar Dome cost tweak.
Merge pull request #4857 from pchote/ra-balance-changelog

Add changelog entry for Radar Dome cost tweak.
add a spectator player that shares shroud with everyone

closes #4607
Merge pull request #4656 from Mailaender/everyone-shroud

Added a spectator player that shares shroud with everyone
moved internal time step setting to Game

player should not be able change it as it is not synced yet
add a pause/slowdown/play/fastforward button for replays

closes #4633
separate World and Ui LastTickTime
use relative tick time intervals
keep the catch up for small delays and truncate larger ones
Add some more robustness against UI-introduced desyncs.
Adjust C&C replay UI.
Tick the game timer status independently of the game rate.
Fix the timestep jank threshold.