Fix for interspersed messages

The way the messages were buffered caused interspersed messages to be
inserted in the middle of CopyData messages disrupting the normal COPY
TO flow.

This fixes it by consuming (adjusting offsets as appropriate) and just
logging them to console, effectively discarding them from the COPY
flow.

copy-to.js

@@ -95,13 +95,20 @@ CopyStreamQuery.prototype._transform = function(chunk, enc, cb) {
     length = chunk.readUInt32BE(offset+Byte1Len)
     if(chunk.length >= (offset + Byte1Len + length)) {
       offset += Byte1Len + Int32Len
-      if (needPush) {
-        var row = chunk.slice(offset, offset + length - Int32Len)
-        this.rowCount++
-        row.copy(buffer, buffer_offset);
-        buffer_offset += row.length;
+      var message = chunk.slice(offset, offset + length - Int32Len)
+      switch(messageCode) {
+        case code.CopyData:
+          this.rowCount++;
+          message.copy(buffer, buffer_offset);
+          buffer_offset += message.length;
+          break;
+        case code.ParameterStatus:
+        case code.NoticeResponse:
+        case code.NotificationResponse:
+          console.log("Got an interspersed message: " + message);
+          break;
       }
-      offset += (length - Int32Len)
+      offset += (length - Int32Len);
     } else {
       // we need more chunks for a complete message
       break;