[Openid-specs-ab] Issue #2084: Subordinate Entity definition (openid/connect)

[peppelinux]

New issue 2084: Subordinate Entity definition
https://bitbucket.org/openid/connect/issues/2084/subordinate-entity-definition

Giuseppe De Marco:

`An Entity accredited by a Trust Anchor or an Intermediate Entity, which can be a Leaf Entity but also an Entity that acts as Intermediate for other Entities.`

We should mention that a Leaf is a Leaf within a specific Federation and under a Trust Anchor.   
At the same time,  the same Entity could be an Intermediate within another federation, under another Trust Anchor.  
  
This is the meaning of the Subordinate Entity definition while at the same this this is not clear within the current text and we need to clarify in which cases an Entity can be both Leaf and Intermediate but in different federations