Make include paths in destiny relative

 * When included by other modules the absolute paths of destiny
   lead to problems

sys/net/destiny/socket.h

@@ -12,7 +12,7 @@
 #include "tcp.h"
 #include "udp.h"
 #include "in.h"
-#include "sys/net/sixlowpan/sixlowip.h"
+#include "../sixlowpan/sixlowip.h"
 
 /*
  * Types

sys/net/destiny/tcp.h

@@ -71,7 +71,7 @@ enum tcp_codes
 
 #define TCP_STACK_SIZE 			1024
 
-#include "sys/net/sixlowpan/sixlowip.h"
+#include "../sixlowpan/sixlowip.h"
 
 typedef struct __attribute__ ((packed)) tcp_mms_o_t
 	{

sys/net/destiny/tcp_hc.c

@@ -12,8 +12,8 @@
 #include "tcp_hc.h"
 #include "socket.h"
 #include "tcp.h"
-#include "sys/net/sixlowpan/sixlowip.h"
-#include "sys/net/net_help/net_help.h"
+#include "../sixlowpan/sixlowip.h"
+#include "../net_help/net_help.h"
 
 #ifdef TCP_HC
 

sys/net/destiny/udp.c

@@ -5,12 +5,12 @@
 
 #include "udp.h"
 #include "msg.h"
-#include "sys/net/sixlowpan/sixlowip.h"
-#include "sys/net/sixlowpan/sixlowpan.h"
+#include "../sixlowpan/sixlowip.h"
+#include "../sixlowpan/sixlowpan.h"
 #include "socket.h"
 #include "in.h"
-#include "sys/net/net_help/net_help.h"
-#include "sys/net/net_help/msg_help.h"
+#include "../net_help/net_help.h"
+#include "../net_help/msg_help.h"
 
 uint16_t udp_csum(ipv6_hdr_t *ipv6_header, udp_hdr_t *udp_header)
 	{