EML

This should be done with the rest of the EML documentation review as found in
bug # 338.

Chnaging target milestone for the major EML bugs to Beta7, which is scheduled
for early to mid March for release. There are likely other bugs that need to be
entered and resolved for this Beta7 release as well, so lets generate a complete
list!

I think we need to carefully consider this list, and possibly revise it. We
originally chose it to correspond to the ISO role codes, but what is important
is that the various roles are 1) understandable, 2) exclusive (more or less),
and 3) comprehensive. If they can't be comprehensive, then we need to consider
making it an extensible domain instead of constraining it to these values.

No matter what we need to precisely define each of the roles that we decide to keep.

This list is now not part of the standard ResponsibleParty. It has been kept in
case some elements want to create a role element. It has been extended so that,
in addition to the enumerated values, any string can also be provided. We still
may want to consider removing it alltogether.

List has been kept, and the list is just a set of suggested terms, but the user
is free to put anything in the role elements. The important roles have been
broken out as individual elements. FIXED.

Original Bugzilla ID was 336