[SPARK-6285][SQL]Remove ParquetTestData in SparkBuild.scala and in README.md

This is a following clean up PR for #5010
This will resolve issues when launching `hive/console` like below:
```
<console>:20: error: object ParquetTestData is not a member of package org.apache.spark.sql.parquet
       import org.apache.spark.sql.parquet.ParquetTestData
```

Author: OopsOutOfMemory <victorshengli@126.com>

Closes #5032 from OopsOutOfMemory/SPARK-6285 and squashes the following commits:

2996aeb [OopsOutOfMemory] remove ParquetTestData

project/SparkBuild.scala

@@ -272,8 +272,7 @@ object SQL {
         |import org.apache.spark.sql.execution
         |import org.apache.spark.sql.functions._
         |import org.apache.spark.sql.test.TestSQLContext._
-        |import org.apache.spark.sql.types._
-        |import org.apache.spark.sql.parquet.ParquetTestData""".stripMargin,
+        |import org.apache.spark.sql.types._""".stripMargin,
     cleanupCommands in console := "sparkContext.stop()"
   )
 }
@@ -304,8 +303,7 @@ object Hive {
         |import org.apache.spark.sql.functions._
         |import org.apache.spark.sql.hive._
         |import org.apache.spark.sql.hive.test.TestHive._
-        |import org.apache.spark.sql.types._
-        |import org.apache.spark.sql.parquet.ParquetTestData""".stripMargin,
+        |import org.apache.spark.sql.types._""".stripMargin,
     cleanupCommands in console := "sparkContext.stop()",
     // Some of our log4j jars make it impossible to submit jobs from this JVM to Hive Map/Reduce
     // in order to generate golden files.  This is only required for developers who are adding new

sql/README.md

@@ -41,7 +41,6 @@ import org.apache.spark.sql.functions._
 import org.apache.spark.sql.hive._
 import org.apache.spark.sql.hive.test.TestHive._
 import org.apache.spark.sql.types._
-import org.apache.spark.sql.parquet.ParquetTestData
 Type in expressions to have them evaluated.
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