Move version reading/writing out of ConnParams

That object is just a container for the current state. Move the I/O
to the classes already doing such stuff.
diff --git a/common/rfb/SConnection.cxx b/common/rfb/SConnection.cxx
index efc26ac..846e97e 100644
--- a/common/rfb/SConnection.cxx
+++ b/common/rfb/SConnection.cxx
@@ -80,7 +80,12 @@
 
 void SConnection::initialiseProtocol()
 {
-  cp.writeVersion(os);
+  char str[13];
+
+  sprintf(str, "RFB %03d.%03d\n", defaultMajorVersion, defaultMinorVersion);
+  os->writeBytes(str, 12);
+  os->flush();
+
   state_ = RFBSTATE_PROTOCOL_VERSION;
 }
 
@@ -104,13 +109,25 @@
 
 void SConnection::processVersionMsg()
 {
+  char verStr[13];
+  int majorVersion;
+  int minorVersion;
+
   vlog.debug("reading protocol version");
-  bool done;
-  if (!cp.readVersion(is, &done)) {
+
+  if (!is->checkNoWait(12))
+    return;
+
+  is->readBytes(verStr, 12);
+  verStr[12] = '\0';
+
+  if (sscanf(verStr, "RFB %03d.%03d\n",
+             &majorVersion, &minorVersion) != 2) {
     state_ = RFBSTATE_INVALID;
     throw Exception("reading version failed: not an RFB client?");
   }
-  if (!done) return;
+
+  cp.setVersion(majorVersion, minorVersion);
 
   vlog.info("Client needs protocol version %d.%d",
             cp.majorVersion, cp.minorVersion);