Create python wrapper for spline.

Change-Id: Ia19bb1500542dd886c78cd201b251e6dff2b1d1b
diff --git a/frc971/control_loops/python/BUILD b/frc971/control_loops/python/BUILD
index c0b71f7..bedd763 100644
--- a/frc971/control_loops/python/BUILD
+++ b/frc971/control_loops/python/BUILD
@@ -77,6 +77,16 @@
 )
 
 py_library(
+    name = "libspline",
+    srcs = [
+        "libspline.py",
+    ],
+    data = [
+        "//frc971/control_loops/drivetrain:spline.so"
+    ],
+)
+
+py_library(
     name = "polydrivetrain",
     srcs = [
         "polydrivetrain.py",