Updated README to include parser option and better instruction for spark packages
Updated README to include parser option and better instruction for spark packages

gasparms/spark-csv,falaki/spark-csv,databricks/spark-csv,methodmill/spark-csv,karenyyng/spark-csv,abridgett/spark-csv,gilv/spark-csv,databricks/spark-csv,ibtawfik/spark-csv,karenyyng/spark-csv,YanjieGao/spark-csv,sunilyadavsky/spark-csv,abridgett/spark-csv,gilv/spark-csv,gasparms/spark-csv,ibtawfik/spark-csv,gasparms/spark-csv,methodmill/spark-csv,falaki/spark-csv,akirakw/spark-csv,sunilyadavsky/spark-csv,akirakw/spark-csv,falaki/spark-csv,sunilyadavsky/spark-csv,YanjieGao/spark-csv,abridgett/spark-csv,saurfang/spark-csv,gilv/spark-csv,databricks/spark-csv,saurfang/spark-csv,YanjieGao/spark-csv