Fixed hive issues to make it stable

This PR fixes multiple hive issues and makes it a stable product under `chef-bach`: The issues that have been fixed are:
Issue #18 Template hv_hive-server2.erb has incorrect command to start hive-server2
Issue #26 hive-site.xml is missing hive.exec.scratchdir parameter
Issue #31 Incompatible MySQL connector installed by Hive-Metastore recipe
Issue #32 Hive Services (Metastore, HiveServer2) doesn't come up after system restart
Issue #34 Hive Services have incorrect start order
Issue #38 Hive Beeline doesn't use scratch directory defined in hive-site.xml
Please add a guard to not download the file should we already have `/usr/share/java/mysql-connector-java-5.1.34.tar.gz`