Merge pull request #3648 from FedericoCeratto/reuse_port

Add SO_REUSEPORT support

lib/pure/net.nim

@@ -129,7 +129,7 @@ type
 
   SOBool* = enum ## Boolean socket options.
     OptAcceptConn, OptBroadcast, OptDebug, OptDontRoute, OptKeepAlive,
-    OptOOBInline, OptReuseAddr
+    OptOOBInline, OptReuseAddr, OptReusePort
 
   ReadLineResult* = enum ## result for readLineAsync
     ReadFullLine, ReadPartialLine, ReadDisconnected, ReadNone
@@ -579,6 +579,7 @@ proc toCInt*(opt: SOBool): cint =
   of OptKeepAlive: SO_KEEPALIVE
   of OptOOBInline: SO_OOBINLINE
   of OptReuseAddr: SO_REUSEADDR
+  of OptReusePort: SO_REUSEPORT
 
 proc getSockOpt*(socket: Socket, opt: SOBool, level = SOL_SOCKET): bool {.
   tags: [ReadIOEffect].} =