Part 2 of 64 bits fixing; the files.

The good news; previously written 64 bits are still valid! All fixes
appeared to be possible in code, no versioning patches needed. :)
That also removes the I AM STUPID 64 bits ban from the code.

The bad news:
I couldn't get a 64 bits Blender running here (ghost-mac issues... it
has to be recoded using Quartz to be able to run 64 bits). So what I
have tested was:

32 bits binary:
  - Appending/linking data from 64 bits file.
  - Reading 64 bits chained library-linked files (file -> file -> etc)
  - Linking 32 bits files with 64 bits files

This has to be tested for 64 bits too. Will drop in IRC now to help.

Note: part 3 is fixing memory issues for addressing > 4 GB data. A first
start has been made for a blenlib API function.

source/blender/blenlib/intern/util.c

@@ -1508,4 +1508,51 @@ void BLI_timestr(double time, char *str)
 	str[11]=0;
 }
 
+/* ************** 64 bits magic, trick to support up to 32 gig of address space *************** */
+/*                only works for malloced pointers (8 aligned)                   */
+
+#ifdef __LP64__ 
+
+#if defined(WIN32) && !defined(FREE_WINDOWS)
+#define PMASK		0x07FFFFFFFFi64
+#else
+#define PMASK		0x07FFFFFFFFll
+#endif
+
+
+int BLI_int_from_pointer(void *poin)
+{
+	long lval= (long)poin;
+	
+	return (int)(lval>>3);
+}
+
+void *BLI_pointer_from_int(int val)
+{
+	static int firsttime= 1;
+	static long basevalue= 0;
+	
+	if(firsttime) {
+		void *poin= malloc(10000);
+		basevalue= (long)poin;
+		basevalue &= ~PMASK;
+		printf("base: %d pointer %p\n", basevalue, poin); /* debug */
+		firsttime= 0;
+		free(poin);
+	}
+	return basevalue | (((long)val)<<3);
+}
+
+#else
+
+int BLI_int_from_pointer(void *poin)
+{
+	return (int)poin;
+}
+void *BLI_pointer_from_int(int val)
+{
+	return (void *)val;
+}
+
+#endif