- Switch master server protocol to dpmaster for better game separation. Based partly on patch by Zack Middleton
- Get rid of ugly cvars sv_heartbeat and cl_gamename and replace with single com_gamename
- Remove sv_flatline. Flatlines are ignored by dpmaster and are considered to be insecure because flatlines can be udp-spoofed.

(cherry picked from commit ba385fa43ce4a38a8e70f578bd87ddd37c26ad27)
Change DLL search path order for external libraries that are linked at runtime, like libcurl or libopenal to:
  * system library paths
  * executable path
  * fs_basepath

(cherry picked from commit 3752b1d7c4c878e2d4be67a88bfc30ebb0b439f0)
Fix cvar flags to get rid of warnings (#2881)

(cherry picked from commit fb34e78b7e340304ea1d5f6cee48e4dba8b731a5)
Fix strange ifdeffery (#5140)

(cherry picked from commit f697df05aa95de28884526a3c35c6691aeb6cb36)
Some more removal of unused code in addition to r2104, by Zack Middleton

(cherry picked from commit e5ddcee71eee7b45ddca9134d779a61512323098)
Fix pak order when reconnecting to a server.
When /connect to the same server is issued while already connected, an initial call to CL_Disconnect will remove all pak file references
and reset the pak order.
Reordering only occurs through FS_Restart, which in turn is called when checksum feed changes. Because we reconnect to the same server,
checksum feed never changes and pak file order is not restored to server order again. With certain pak file constellations between client/server,
this may result in an inability to load files from paks which are not correctly detected as referenced paks.

(cherry picked from commit 8ab958fab9a4eb69b922f4247ffc792564edddcb)
Updated related ioquake3 commit