New text: Attributes with no equality matching rule

["Kurt D. Zeilenga" <Kurt@OpenLDAP.org>]

To address this issue, I suggest the following changes be made
to [Models]:

Delete from 2.3 the sentence:
  If the attribute type is defined with no equality matching rule,
  two values are equivalent if and only if they are identical.

Add after first paragraph of section 2.5.1:
  If no equality matching is specified for the attribute type:     
    - the attribute (of the type) cannot be used for naming;            
    - individual values of a multi-valued attribute cannot be
      added or deleted;
    - attribute value assertions using values of such a type
      cannot be performed.

  Otherwise, the equality matching rule is to be used for the
  purposes of evaluating attribute value assertions concerning
  the attribute type.

I note that I didn't say anything about syntax checking of
values as this is already covered in section 2.5.4.  Also,
I didn't think it necessary to call out comparisons from AVAs
(given we describe compares in terms of AVAs).

Comments?

Kurt