Update the sensor ratios

Pull sensor output ratios from the cad.  This process found that the
hood was being operated in such a way that the hood encoder was blowing
past 360 degrees and wrapping.  So fix that too.

Change-Id: I896458bb81461e7f032a464faa0b78e07d257c10
diff --git a/frc971/constants.h b/frc971/constants.h
index a52add2..debfb55 100644
--- a/frc971/constants.h
+++ b/frc971/constants.h
@@ -98,6 +98,8 @@
   double upper;
 
   double middle() const { return (lower_hard + upper_hard) / 2.0; }
+
+  double range() const { return upper_hard - lower_hard; }
 };
 
 }  // namespace constants