Fix translation files and update documentation (#12595)

scripts/po2json.sh

@@ -0,0 +1,27 @@
+# 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.
+
+for file in $( find superset/translations/** );
+do
+  extension=${file##*.}
+  filename="${file%.*}"
+  if [ $extension == "po" ]
+  then
+    po2json --domain superset --format jed1.x $file $filename.json
+    ./superset-frontend/node_modules/.bin/prettier --write $filename.json
+  fi
+done