V3.6.1

This release just has 3 fixes in it. One to fix a regression for STDIO when a dataframe is empty; still create the empty dataset. That was a break in 3.6.0. Fix an import error that can happen; depends on maybe what other modules you have installed? Either way, it's fixed for all cases now. That was in IOM access method. And, there was a code path in tail() where an error could happen. Fixed that too in this release. That's all.