Fix T37488: Crash with --debug reading userpref.blend

Issue was in fact caused by wrong DNA storage, which
apparently was considering unsigned long as just 4
bytes here.

Now use uint64_t to be sure timestamp does fit into
storage on all the platforms.

Thanks Campbell for help looking in the issue.

source/blender/blenkernel/BKE_main.h

@@ -53,7 +53,7 @@ typedef struct Main {
 	char name[1024]; /* 1024 = FILE_MAX */
 	short versionfile, subversionfile;  /* see BLENDER_VERSION, BLENDER_SUBVERSION */
 	short minversionfile, minsubversionfile;
-	unsigned long build_commit_timestamp; /* commit's timestamp from buildinfo */
+	uint64_t build_commit_timestamp; /* commit's timestamp from buildinfo */
 	char build_hash[16];  /* hash from buildinfo */
 	short recovered;	/* indicate the main->name (file) is the recovered one */
 	

source/blender/makesdna/DNA_fileglobal_types.h

@@ -48,8 +48,8 @@ typedef struct FileGlobal {
 	struct Scene *curscene;
 	int fileflags;
 	int globalf;
-	unsigned long build_commit_timestamp;  /* commit timestamp from buildinfo */
-	char build_hash[12];  /* hash from buildinfo */
+	uint64_t build_commit_timestamp;  /* commit timestamp from buildinfo */
+	char build_hash[16];  /* hash from buildinfo */
 	/* file path where this was saved, for recover */
 	char filename[1024]; /* 1024 = FILE_MAX */
 } FileGlobal;

source/gameengine/Ketsji/KX_PythonMain.h

@@ -32,6 +32,7 @@
 #ifndef __KX_PYTHON_MAIN__
 #define __KX_PYTHON_MAIN__
 
+#include "BLI_sys_types.h"
 #include "BKE_main.h"
 #include "DNA_scene_types.h"
 extern "C" char *KX_GetPythonMain(struct Scene* scene);