(theoretically) got encoders working

Everything up to sending all 8 encoder values should work now (including
the packet format + header information, bootloader (fixed some bugs in
the UART code for that), etc).
diff --git a/bbb_cape/src/cape/peripherial_usage.notes b/bbb_cape/src/cape/peripherial_usage.notes
index 5f361f7..b0dac40 100644
--- a/bbb_cape/src/cape/peripherial_usage.notes
+++ b/bbb_cape/src/cape/peripherial_usage.notes
@@ -24,8 +24,14 @@
 [encoders]
 encoder
   TIM1,TIM2,TIM3,TIM4,TIM5,TIM8
+  EXTI0,EXTI1,EXTI2,EXTI3
+  EXTI0_IRQ:0,EXTI1_IRQ:0,EXTI2_IRQ:0,EXTI3_IRQ:0
+
 
 [sensor packet sending]
 fill_packet
   TIM6
+
+[utilities]
+crc
   CRC