Add raw write test to example.c

Allow the data_len to be specified as -1 to use strlen() on data.

src/xpdoor/example.c

@@ -9,8 +9,13 @@ int main(int argc, char **argv)
 	cprintf("Drop path: %s\r\n",xpd_info.drop.path?xpd_info.drop.path:"<Unknown>");
 
 	cprintf("Welcome %s!\r\n\r\n",xpd_info.drop.user.full_name?xpd_info.drop.user.full_name:"<unknown>");
+
+	cputs("Press <ENTER> to try out raw writes...");
+	getch();
+
+	xpd_rwrite("\x1b[2J\x1b[1;1H\x1b[32mTest\r\n", -1);
 	
-	cputs("Press <ENTER> to exit: ");
+	cputs("\r\nPress <ENTER> to exit: ");
 	getch();
 	cputs("\r\n");
 	xpd_exit();

src/xpdoor/xpdoor.c

@@ -321,6 +321,9 @@ int xpd_rwrite(const char *data, int data_len)
 {
 	struct text_info	ti;
 
+	if(data_len == -1)
+		data_len=strlen(data);
+
 	/* Set up cterm to match conio */
 	gettextinfo(&ti);
 	cterm.x=ti.winleft+ti.curx-1;