Class A Rule Simplification

Class A is only intended to provide backwards compatibility & is not
used in any of the respective wallet implementations or for any features
other than basic simple send.  Thus the effort being expended on Class A
does not correlate with its utility to the project and this pull is
intended to put Class A to bed so we can move onto other more useful
work.
Qualified that one of the two same valued outputs must be the data address & that the two same valued outputs are in addition to the Exodus output.
Clarified wording
Accomodate Tachikoma's point on human control

Tachikoma raised a valid point noting that users have control over
outputs but not seqnums, thus the human controlled aspect (outputs)
should take precedence in conflicts.  Accepted & modified to accomodate.
Merge pull request #36 from zathras-crypto/master

Class A Rule Simplification