Add jackson license (#202)

LICENSE.jackson.txt

@@ -0,0 +1,13 @@
+This copy of Jackson JSON processor is licensed under the
+Apache (Software) License, version 2.0 ("the License").
+See the License for details about distribution rights, and the
+specific rights regarding derivate works.
+
+You may obtain a copy of the License at:
+
+http://www.apache.org/licenses/
+
+A copy is also included with both the the downloadable source code package
+and jar that contains class bytecodes, as file "ASL 2.0". In both cases,
+that file should be located next to this file: in source distribution
+the location should be "release-notes/asl"; and in jar "META-INF/"