BUG: Need to include header <new> to use placement new syntax. Really this...

BUG: Need to include header <new> to use placement new syntax.  Really this should be fixed by replacing the stream buffer to set a new string instead of reconstructing the object, but this will require quite a bit of work to do portably.

kwsys_ios_sstream.h.in

@@ -50,6 +50,7 @@
 // ostringstream and istringstream classes.
 
 # include <@KWSYS_NAMESPACE@/stl/string>
+# include <new> // Need placement operator new.
 
 namespace @KWSYS_NAMESPACE@_ios
 {