Clarify YAML docs
The problem I am trying to solve: If you try to understand what methods do
YAML have, and what parameters, say,
YAML.load_file accept, the "official" docs look pretty unhelpful, saying, basically "This is not the docs you are looking for".
The Psych library is mentioned and even hyperlinked, yet it mentioned as an "underlying implementation", like "something low-level that helps stdlib's YAML to do the job, don't think about Psych".
So, I felt it as a necessity to add a clarification that Psych, in fact, IS YAML, and all options and methods are documented there.