[SPARK-12600][SQL] Remove deprecated methods in Spark SQL

dev/run-tests.py

project/MimaExcludes.scala

python/pyspark/__init__.py

python/pyspark/sql/__init__.py

python/pyspark/sql/column.py

python/pyspark/sql/context.py

python/pyspark/sql/dataframe.py

python/pyspark/sql/functions.py

python/pyspark/sql/readwriter.py

python/pyspark/sql/tests.py

...ache/spark/sql/catalyst/util/LegacyTypeStringParser.scala

.../src/main/scala/org/apache/spark/sql/types/DataType.scala

...c/main/scala/org/apache/spark/sql/types/DecimalType.scala

...rc/main/scala/org/apache/spark/sql/types/StructType.scala

sql/core/src/main/scala/org/apache/spark/sql/Column.scala

sql/core/src/main/scala/org/apache/spark/sql/DataFrame.scala

...src/main/scala/org/apache/spark/sql/DataFrameReader.scala

...core/src/main/scala/org/apache/spark/sql/SQLContext.scala

...k/sql/execution/datasources/parquet/ParquetRelation.scala

sql/core/src/main/scala/org/apache/spark/sql/functions.scala