Split out ServerParams from ConnParams

We need to track different things in the server and client, so
separate things to two independent structures to keep things more
clear.
diff --git a/common/rfb/RREDecoder.h b/common/rfb/RREDecoder.h
index f89fef4..f47edda 100644
--- a/common/rfb/RREDecoder.h
+++ b/common/rfb/RREDecoder.h
@@ -27,9 +27,9 @@
     RREDecoder();
     virtual ~RREDecoder();
     virtual void readRect(const Rect& r, rdr::InStream* is,
-                          const ConnParams& cp, rdr::OutStream* os);
+                          const ServerParams& server, rdr::OutStream* os);
     virtual void decodeRect(const Rect& r, const void* buffer,
-                            size_t buflen, const ConnParams& cp,
+                            size_t buflen, const ServerParams& server,
                             ModifiablePixelBuffer* pb);
   };
 }