Move I_StartTic call to G_BuildTiccmd, since this always has to be called; eventually this will be done between frames though
memset player.cmd before G_BuildTiccmd in singleplayer, fixes singleplayer
Further hide overlay behind ifdef's; add CMake option to enable

Disable ENet's range coder, it uses a lot of CPU; need to make optional
at some point (somehow...)

Redirect sound logging to the sound log from the sync log

Work on separating out various sync ideas with ifdef's.
Predict 'lost' TICs; fixes missing sound problems
Refactor rendering extra frames; fixes a couple bugs

Only call I_GetTime_SaveMS when running a new TIC clientside

Call M_Ticker directly instead of multiple times in render_menu

Prefix all client-specific static variables in n_main with cl_

Continuing to work on uncapped jitter:
  - Looks to be lag-related
  - Jitter "settles down" after initial connection with no lag