Reorganise unarchiving functions, more code re-use, only does single pass(no more linked lists), basis for supporting a cpio (and cheaper untar) applet, but cpio applet isnt included in this.

It effects ar, dpkg-deb applets only

archival/dpkg_deb.c

@@ -26,7 +26,7 @@ extern int dpkg_deb_main(int argc, char **argv)
 	char *output_buffer = NULL;
 	int opt = 0;
 	int arg_type = 0;
-	int deb_extract_funct = 0;	
+	int deb_extract_funct = extract_create_dirs;	
 	
 	const int arg_type_prefix = 1;
 	const int arg_type_field = 2;