re-re-revision on Section 4 for consistency in ordering (by group) of requirements in terms of MUST>MUST NOT>SHOULD>SHOULD NOT>MAY as well as formatting consistency and order consistency for subsections of Description>Rationale>Requirements>Details>Example throughout all 4.x
Merge pull request #305 from aaronesilvers/master

Section 4 revisited for technical edits (non-breaking)