Refactored unwrap class from y2018 code to frc971 directory.

Change-Id: I375e1a2cf875e89944d514f333295867d1a3437b
diff --git a/frc971/zeroing/BUILD b/frc971/zeroing/BUILD
index fe95bdc..b066dea 100644
--- a/frc971/zeroing/BUILD
+++ b/frc971/zeroing/BUILD
@@ -73,3 +73,14 @@
         "//aos/testing:googletest",
     ],
 )
+
+cc_test(
+    name = "unwrap_test",
+    srcs = [
+        "unwrap_test.cc",
+    ],
+    deps = [
+        ":wrap",
+        "//aos/testing:googletest",
+    ],
+)