Create .npmignore (#419)

exclude unnecessary files to be included in npm package

Author: davidkhala

.npmignore

@@ -0,0 +1,40 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# 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.
+#
+.github
+build-support
+docs
+examples
+perf
+pkg
+tests
+# linting
+.clang-format
+.eslintignore
+.eslintrc.json
+# ts
+tsconfig.json
+tslint.json
+tstest.ts
+typedoc.json
+
+# license
+license-checker-config.json
+license-header.txt
+
+