NEW ISSUE [Primer] : Update references to interoperability in Ignorable Policy Expressions section

Re: NEW ISSUE: [GUIDELINES] Use of @wsp:optional and @wsp:Ignorable o n the same assertionDescription: Ignorable Expressions section refers to the interoperabilty term in the 2nd
sentence of the first paragraph. This is on-the-wire interoperability.
The section also implicitly refers to the possible impact such expressions can
have on the WS-Policy level interoperability in the last sentence of the
section. This last message should be highlighted by saying that the
ignorableness is at the discretion of the policy consumer

Justification : the policy author should be well aware that by marking the
assertion as wsp:ignorable does not guarantee this assertion be universally
ignored.

Target : WS-Policy Primer, Section 2.7

Proposal : Update the last sentence : "Please note that the ignorableness is at
the discretion of policy consumers therefore ignorable assertions may have an
impact on determining compatibility of policies"
Also, optionally, consider updating the interop term in the first pararaph by
qualifying it with "on-the-wire" or something similar