add NOTICE and CODE_OF_CONDUCT files

Author: SethTisue

CODE_OF_CONDUCT.md

@@ -0,0 +1,7 @@
+all repositories in these organizations:
+
+* [scala](https://github.com/scala)
+* [scalacenter](https://github.com/scalacenter)
+* [lampepfl](https://github.com/lampepfl)
+
+are covered by the Scala Code of Conduct: https://scala-lang.org/conduct/

NOTICE

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+scala-xml
+Copyright (c) 2002-2019 EPFL
+Copyright (c) 2011-2019 Lightbend, Inc.
+
+scala-xml includes software developed at
+LAMP/EPFL (https://lamp.epfl.ch/) and
+Lightbend, Inc. (https://www.lightbend.com/).
+
+Licensed under the Apache License, Version 2.0 (the "License").
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.