Added network load balancing

- Guests can now attempt to match latency with the arbitrator.
(net_loadbalance)
- Added althud feature to show arbitrator and local latency.
(hud_showlag 1 is on for netgames, 2 is always on)
Further refinements to network balancing

- Added delay times of all players to the scoreboard
- Removed balancing from packet-server (tried it, didn't work)
- Calculations remove an extra tic to account for possible bias
New extratic method

- Extratic changed to server var, that can be changed at any time
(net_extratic)
- Added net_extratic 2 which resends all unconfirmed tics
- Corrected bad variable typo in delay reporting
Bumped net version
Extratics mode 3 didn't work well

- Removed Extratics mode 3
- Fixed a typo
Don't need to MAX() mode 2
Added menu options for network settings
Made delay updates less erratic
Player prediction now updates listener
Stop negative tic counts from corrupting messages
Shifted netmode reporting for guests

- The netmode is now reported after a guest has received it.
- Minor code cleanup
Readded -extratic for compatibility with launchers
Added silent line teleport prediction

- Allow activation of line teleport specials during prediction
- Moved prediction functions to improve uncapped framerates
Added standard teleports to line prediction

- Added standard teleports to line prediction
- Menudef for line special prediction
Don't balance if already the slowest node

- Network balancing shouldn't be run if already too far behind
- Don't save network settings
- Added net_fakelatency for debug builds
Final changes to balancing