Added y2018 wpilib_interface, and constants

Change-Id: I9499fc4fbb34434372583e8e2a572740b60a4715
diff --git a/y2018/control_loops/superstructure/arm/BUILD b/y2018/control_loops/superstructure/arm/BUILD
index 6961dd3..6104568 100644
--- a/y2018/control_loops/superstructure/arm/BUILD
+++ b/y2018/control_loops/superstructure/arm/BUILD
@@ -6,6 +6,7 @@
     hdrs = [
         "trajectory.h",
     ],
+    visibility = ["//visibility:public"],
     deps = [
         ":dynamics",
         "//frc971/control_loops:dlqr",
@@ -37,6 +38,7 @@
     hdrs = [
         "dynamics.h",
     ],
+    visibility = ["//visibility:public"],
     deps = [
         "//frc971/control_loops:runge_kutta",
         "//third_party/eigen",
@@ -86,6 +88,7 @@
     hdrs = [
         "ekf.h",
     ],
+    visibility = ["//visibility:public"],
     deps = [
         ":dynamics",
         "//frc971/control_loops:jacobian",