rename "whirl" to "tornado"

tornado/doc/mech.fpd

@@ -31,7 +31,7 @@ frame cpu {
 	rect __0 . w
 }
 
-package "whirl"
+package "tornado"
 unit mm
 
 table

tornado/fw/Makefile

@@ -1,5 +1,5 @@
 #
-# Makefile - Makefile of the Whirl firmware 
+# Makefile - Makefile of the Tornado firmware 
 #
 # Written 2012 by Werner Almesberger
 # Copyright 2012 by Werner Almesberger
@@ -12,7 +12,7 @@
 
 SHELL = /bin/bash
 
-NAME = whirl
+NAME = tornado
 
 CFLAGS = -g -mmcu=$(CHIP) \
 	 -DBOOT_ADDR=$(BOOT_ADDR) \