Move PDU utils into their own file

include/tins/utils.h

@@ -30,30 +30,14 @@
 #ifndef TINS_UTILS_H
 #define TINS_UTILS_H
 
-#include "macros.h"
-#include <string>
-#include <stdint.h>
-#include "ip_address.h"
-#include "ipv6_address.h"
-#include "pdu.h"
-#include "detail/type_traits.h"
 #include "utils/checksum_utils.h"
 #include "utils/frequency_utils.h"
 #include "utils/routing_utils.h"
 #include "utils/resolve_utils.h"
-
-// Fix for Windows interface define on combaseapi.h
-#undef interface
-
+#include "utils/pdu_utils.h"
+ 
 namespace Tins {
 
-class NetworkInterface;
-class PacketSender;
-class PDU;
-class IPv6Address;
-template <size_t n>
-class HWAddress;
-
 /** 
  * \brief Network utils namespace.
  *
@@ -63,45 +47,6 @@ class HWAddress;
  */
 namespace Utils {
 
-/**
- * \brief Converts a PDUType to a string.
- * \param pduType The PDUType to be converted.
- * \return A string representation, for example "DOT11_QOS_DATA".
- */
-TINS_API std::string to_string(PDU::PDUType pduType);
-
-template <typename T>
-struct is_pdu {  
-    template <typename U>
-    static char test(typename U::PDUType*);
-     
-    template <typename U>
-    static long test(...);
- 
-    static const bool value = sizeof(test<T>(0)) == 1;
-};
-
-/**
- * Returns the argument.
- */
-inline PDU& dereference_until_pdu(PDU& pdu) {
-    return pdu;
-}
-
-/**
- * \brief Dereferences the parameter until a PDU is found.
- * 
- * This function dereferences the parameter until a PDU object
- * is found. When it's found, it is returned. 
- * 
- * \param value The parameter to be dereferenced.
- */
-template<typename T> 
-inline typename Internals::enable_if<!is_pdu<T>::value, PDU&>::type 
-dereference_until_pdu(T& value) {
-    return dereference_until_pdu(*value);
-}
-
 } // Utils
 } // Tins