Import google/walt

Cloned from https://github.com/google/walt.git without modification.

Bug: 36896528
Test: N/A
diff --git a/CONTRIBUTORS b/CONTRIBUTORS
new file mode 100644
index 0000000..772f3f8
--- /dev/null
+++ b/CONTRIBUTORS
@@ -0,0 +1,15 @@
+# People who have agreed to one of the CLAs and can contribute patches.
+# The AUTHORS file lists the copyright holders; this file
+# lists people.  For example, Google employees are listed here
+# but not in AUTHORS, because Google holds the copyright.
+#
+# https://developers.google.com/open-source/cla/individual
+# https://developers.google.com/open-source/cla/corporate
+#
+# Names should be added to this file as:
+#     Name <email address>
+
+Mark Koudritsky <kamrik@google.com>
+Don Turner <donturner@google.com>
+Benjamin Fair <benjaminfair@google.com>
+Philip Quinn <pquinn@google.com>