Log deprecation warning if dataset name contains "."

I use the demo code (ref. Kite SDK documentation) to create a dataset into HDFS. The uri is dataset:hdfs:/tmp/4.2. I found two things wired.

1. The dataset has nothing to do with Hive/HCatlog, but I saw a warning of the dataset name. I do not read any notice about restriction for a HDFS folder name.

WARN spi.Compatibility: Hive incompatible: Dataset name par4.2 is not alphanumeric (plus '_')

2. The dataset will be actually created into hdfs:/tmp/4/2.