Add tests for mysql-connector-java and postgresql-jdbc packages

ChefSpec Coverage report generated...

  Total Resources:   106
  Touched Resources: 85
  Touch Coverage:    80.19%
Move hive package check into its own section and do symlink test for CentOS
Add ubuntu context
Add directory and execute checks

ChefSpec Coverage report generated...

  Total Resources:   109
  Touched Resources: 91
  Touch Coverage:    83.49%