Arm works

Added gravity and calibrated it.  Terifying...

Change-Id: I70babb1cd3b83ddd7a81f06fb2a75cefd55bcdb8
diff --git a/y2018/control_loops/superstructure/BUILD b/y2018/control_loops/superstructure/BUILD
index c8b0b84..1d52ab4 100644
--- a/y2018/control_loops/superstructure/BUILD
+++ b/y2018/control_loops/superstructure/BUILD
@@ -26,6 +26,7 @@
         "//aos/common/controls:control_loop",
         "//frc971/control_loops:queues",
         "//y2018:constants",
+        "//y2018/control_loops/superstructure/arm",
         "//y2018/control_loops/superstructure/intake",
     ],
 )