Added journal volume meta box

Added ability to add volume, issue, fpage and lpage to articles and output to XML.
Added XML code for journal details
Changed Publisher ISSN to Journal ISSN
Changed default DOI to my personal DOI input
Hard coded subject in XML

Added subj-group-type="heading to subj-group
Missed the pub_issn in the output. Fixed!
Added contrib-type="author" to contrib
Added ppub date (same as epub for now)
Added degrees to author, multiple institutions, copyright, history, abbrev

- Added ability to add multiple instutitions to authors separating with a pipe character.
- Made institutions into textareas for more room to enter multiple institutions.
- Institutions are now properly added with xref links and listed in aff with sup tags (not an easy task!)
- Uncommented email
- Added copyright
- Added history using custom fields in the journal details box for received and accepted.
- Added abbrev to XML