Stop abusing InputHandler class for write class

The handler is for incoming data and we should not be abusing that
class for the writer class. Do proper write prototypes for the
relevant functions.
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 1c0503c..14163aa 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -520,7 +520,7 @@
     vlog.debug("Sending clipboard data (%d bytes)", (int)strlen(buffer));
 
     try {
-      cc->writer()->clientCutText(buffer, ret);
+      cc->writer()->writeClientCutText(buffer, ret);
     } catch (rdr::Exception& e) {
       vlog.error("%s", e.str());
       exit_vncviewer(e.str());
@@ -666,7 +666,7 @@
   if (!viewOnly) {
     if (pointerEventInterval == 0 || buttonMask != lastButtonMask) {
       try {
-        cc->writer()->pointerEvent(pos, buttonMask);
+        cc->writer()->writePointerEvent(pos, buttonMask);
       } catch (rdr::Exception& e) {
         vlog.error("%s", e.str());
         exit_vncviewer(e.str());
@@ -689,7 +689,8 @@
   assert(self);
 
   try {
-    self->cc->writer()->pointerEvent(self->lastPointerPos, self->lastButtonMask);
+    self->cc->writer()->writePointerEvent(self->lastPointerPos,
+                                          self->lastButtonMask);
   } catch (rdr::Exception& e) {
     vlog.error("%s", e.str());
     exit_vncviewer(e.str());
@@ -756,9 +757,9 @@
   try {
     // Fake keycode?
     if (keyCode > 0xff)
-      cc->writer()->keyEvent(keySym, 0, true);
+      cc->writer()->writeKeyEvent(keySym, 0, true);
     else
-      cc->writer()->keyEvent(keySym, keyCode, true);
+      cc->writer()->writeKeyEvent(keySym, keyCode, true);
   } catch (rdr::Exception& e) {
     vlog.error("%s", e.str());
     exit_vncviewer(e.str());
@@ -790,9 +791,9 @@
 
   try {
     if (keyCode > 0xff)
-      cc->writer()->keyEvent(iter->second, 0, false);
+      cc->writer()->writeKeyEvent(iter->second, 0, false);
     else
-      cc->writer()->keyEvent(iter->second, keyCode, false);
+      cc->writer()->writeKeyEvent(iter->second, keyCode, false);
   } catch (rdr::Exception& e) {
     vlog.error("%s", e.str());
     exit_vncviewer(e.str());