Fix dead code Scala compiler warnings

[jbaiera]

Subtask of #969

Dead code should be removed to clear the existing warnings out.

/Users/james.baiera/Documents/source/elasticsearch-hadoop/spark/sql-20/src/main/scala/org/elasticsearch/spark/sql/DataFrameValueWriter.scala:112: dead code following this construct
    value match {
          ^
/Users/james.baiera/Documents/source/elasticsearch-hadoop/spark/sql-20/src/main/scala/org/elasticsearch/spark/sql/DataFrameValueWriter.scala:112: dead code following this construct
    value match {
    ^

[takezoe]

These warnings has been fixed in #940.

[jbaiera]

@takezoe Indeed they were. Looks like I was running this on a branch that didn't have #940. Closing this.