NEW ISSUE: Change 'optional' and 'required' in section 3 to RFC 2119OPTIONAL and REQUIRED

Title: Change 'optional' and 'required' in section 3 to RFC 2119 
OPTIONAL and REQUIRED

Description:
Section 3 uses 'optional' and 'required' to mean the same thing as 
'optional' and 'required' in RFC 2119. To keep the style consistent, 
these should be capitalized.

Justification:
Section 3 uses 'optional' and 'required' to mean the same thing as 
'optional' and 'required' in RFC 2119. To keep the style consistent, 
these should be capitalized.
For example: page 15 line 342, page 15 line 336 in [1].

Target: core

Type: editorial

Proposal:

Change all occurrences of 'required' to 'REQUIRED' and 'optional' to 
'OPTIONAL' in section 3.

Related issues: none

[1] 
http://www.oasis-open.org/apps/org/workgroup/ws-rx/download.php/14548/wsrm-1.1-spec-wd-03.pdf