-Add LogChannel class to provide multiple channels of debug logging for the networking subsystem.
-Individual channels can be toggled and written to stdout, stderr, or to text files.

git-svn-id: http://odamex.net/svn/root/branches/net3-base@4590 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Change Net_LogPrintf to accept a log channel name parameter and automatically insert the name of the function calling Net_LogPrintf.

git-svn-id: http://odamex.net/svn/root/branches/net3-base@4591 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Net_LogPrintf2 should first verify that output to the specified log channel is enabled in the interest of efficiency.

git-svn-id: http://odamex.net/svn/root/branches/net3-base@4592 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Add the console commands net_logchannames to list all of the networking log channels and net_logchandest to specify a filename for the output from a networking log channel.

git-svn-id: http://odamex.net/svn/root/branches/net3-base@4593 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Add global OString constants for log channel names.
-Rework Net_LogPrintf2 slightly to be more efficient.

git-svn-id: http://odamex.net/svn/root/branches/net3-base@4594 b0bcef46-2027-0410-bd56-ab726e9a1d04