Add a convenient vector wrapper

Change-Id: I9b620d065f69909e5be74cd0df802bf9e57eb4d0
diff --git a/aos/vision/math/BUILD b/aos/vision/math/BUILD
new file mode 100644
index 0000000..c52e963
--- /dev/null
+++ b/aos/vision/math/BUILD
@@ -0,0 +1,21 @@
+cc_library(
+  name = 'vector',
+  hdrs = [
+    'vector.h',
+  ],
+  deps = [
+    '//third_party/eigen',
+  ],
+)
+
+cc_test(
+  name = 'vector_test',
+  srcs = [
+    'vector_test.cc',
+  ],
+  deps = [
+    ':vector',
+    '//aos/testing:googletest',
+  ],
+  size = 'small',
+)