Create Python wrapper for distance_spline.

Also reformatted libspline.py
Also made the constructor for Spline more useful.

Change-Id: I0e54a54df7c872ba0c06f9d6ad414d2880c157d7
diff --git a/frc971/control_loops/drivetrain/BUILD b/frc971/control_loops/drivetrain/BUILD
index c3ea79e..8f98953 100644
--- a/frc971/control_loops/drivetrain/BUILD
+++ b/frc971/control_loops/drivetrain/BUILD
@@ -268,6 +268,17 @@
     ],
 )
 
+cc_binary(
+    name = "spline.so",
+    srcs = ["libspline.cc"],
+    deps = [
+        ":distance_spline",
+        ":spline",
+        "//third_party/eigen",
+    ],
+    linkshared=True,
+)
+
 cc_test(
     name = "spline_test",
     srcs = [
@@ -294,16 +305,6 @@
     ],
 )
 
-cc_binary(
-    name = "spline.so",
-    srcs = ["libspline.cc"],
-    deps = [
-        ":spline",
-        "//third_party/eigen",
-    ],
-    linkshared=1,
-)
-
 cc_test(
     name = "distance_spline_test",
     srcs = [