Allows reading decimal columns with or without codegen. Includes tests
based on a data file posted on HIVE-5823.
Change-Id: Ie541c6b98bd24543691850cb45a434af60b5a5a6
(cherry picked from commit 6983dcefdf70cce14724e17d03bc061ffb8f671c)
Reviewed-on: http://gerrit.ent.cloudera.com:8080/2596
Reviewed-by: Skye Wanderman-Milne <skye@cloudera.com>
Tested-by: jenkins