IMPALA-1310: Handle creating parquet files with many columns

The parquet writer assumes a minimum size per column, but for very wide
tables with enough columns (> ~1300 columns for 256 MB parquet file, >
~2600 for 512 MB file, etc)), this will not be true. If the user did not
set the parquet_file_size query option, then automatically adjust the
file size to satisfy the minimum size per column constraint.  Otherwise,
if the query option was set, always use that value but return an error
if the size is not sufficient.

Finally, set the default parquet file size back to 256 MB now that the
test has been fixed.

Change-Id: Ie66cf50d429993d205e278df75f73a04a80b0009
Reviewed-on: http://gerrit.sjc.cloudera.com:8080/4558
Reviewed-by: Nong Li <nong@cloudera.com>
Tested-by: jenkins