Fixed code that generated the following warnings under Clang:
-Wdeprecated-non-prototype
-Wsingle-bit-bitfield-constant-conversion warnings

This commit adds a verification before setting the servername console
variable. We now check that it fits within the MAXSERVERNAME length and
we cancel setting it if it doesn't.
Letting the servername be more than MAXSERVERNAME could lead to crashes
when trying to edit the server name from the menu so, we now avoid
those.

Update skin cvar from character select and compare against cvar when warping to map without character select

This reverts commit e67e225f.

This reverts commit 3a09c475.

There was a possible buffer overflow if you tried setting a console var
that had the CV_NETVAR and that was of the string type.
The overflow would happen if you were trying to set the console variable
while in a multiplayer / netgame state.

This commit just increases the size of buf to account for everything
that needs to be written to it.