boost: split stream classes out of serialize.h

serialization now has no dependencies.

src/allocators.h

@@ -9,6 +9,7 @@
 #include <map>
 #include <string>
 #include <string.h>
+#include <vector>
 
 #include <boost/thread/mutex.hpp>
 #include <boost/thread/once.hpp>
@@ -261,4 +262,7 @@ struct zero_after_free_allocator : public std::allocator<T> {
 // This is exactly like std::string, but with a custom allocator.
 typedef std::basic_string<char, std::char_traits<char>, secure_allocator<char> > SecureString;
 
+// Byte-vector that clears its contents before deletion.
+typedef std::vector<char, zero_after_free_allocator<char> > CSerializeData;
+
 #endif // BITCOIN_ALLOCATORS_H