[SPARK-9304] [BUILD] Improve backwards compatibility of SPARK-8401

Add back change-version-to-X.sh scripts, as wrappers for new script, for backwards compatibility

Author: Sean Owen <sowen@cloudera.com>

Closes #7639 from srowen/SPARK-9304 and squashes the following commits:

9ab2681 [Sean Owen] Add deprecation message to wrappers
3c8c202 [Sean Owen] Add back change-version-to-X.sh scripts, as wrappers for new script, for backwards compatibility

dev/change-version-to-2.10.sh

+#!/usr/bin/env bash
+
+#
+# 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.
+#
+
+# This script exists for backwards compability. Use change-scala-version.sh instead.
+echo "This script is deprecated. Please instead run: change-scala-version.sh 2.10"
+
+$(dirname $0)/change-scala-version.sh 2.10

dev/change-version-to-2.11.sh

+#!/usr/bin/env bash
+
+#
+# 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.
+#
+
+# This script exists for backwards compability. Use change-scala-version.sh instead.
+echo "This script is deprecated. Please instead run: change-scala-version.sh 2.11"
+
+$(dirname $0)/change-scala-version.sh 2.11