Remove unnecessary usage of #include <iostream>. Rename templated impls from .cc to -impl.h.

src/examples/ntester.cc

@@ -36,7 +36,7 @@
 #include "user.h"
 #include "fatal_assert.h"
 #include "pty_compat.h"
-#include "networktransport.cc"
+#include "networktransport-impl.h"
 #include "select.h"
 
 using namespace Network;

src/examples/parse.cc

@@ -42,7 +42,6 @@
 #include <wchar.h>
 #include <assert.h>
 #include <wctype.h>
-#include <iostream>
 #include <typeinfo>
 #include <termios.h>
 

src/examples/termemu.cc

@@ -42,7 +42,6 @@
 #include <wchar.h>
 #include <assert.h>
 #include <wctype.h>
-#include <iostream>
 #include <typeinfo>
 #include <sys/ioctl.h>
 #include <sys/stat.h>