Move analytic fns test case for decimal to decimal.test

Change-Id: Ic6e02484f47f9a9c47924850c8cf12daf8574c8c
Reviewed-on: http://gerrit.sjc.cloudera.com:8080/4449
Reviewed-by: Ippokratis Pandis <ipandis@cloudera.com>
Tested-by: jenkins