Add NOTICE file for mcuboot from ASF

Signed-off-by: Sterling Hughes <sterling@runtime.io>
Signed-off-by: Fabio Utzig <utzig@apache.org>
diff --git a/NOTICE b/NOTICE
new file mode 100644
index 0000000..4ba7354
--- /dev/null
+++ b/NOTICE
@@ -0,0 +1,8 @@
+Apache Mynewt
+Copyright 2015-2017 The Apache Software Foundation
+
+This product includes software developed at
+The Apache Software Foundation (http://www.apache.org/).
+
+Portions of this software were developed at
+Runtime Inc, copyright 2015.