Fix YAML flow maps
Created by: ibaned
See #3023 (closed) for user issue, this PR adds both a reproducing unit test and a fix to the YAML ParameterList builder.
@trilinos/teuchos
Description
This PR fixes and adds a test for flow-style maps in YAML files defining a Teuchos ParameterList.
Motivation and Context
As seen in #3023 (closed), users find it useful to be able to express parameters in flow style. Also I never intended for this to not work, so in some sense it is an oversight bug.
How Has This Been Tested?
A custom build of Teuchos passed all unit tests including the one added.