Minor SEO bugs from Google Scholar

[tdonohue]

From the feedback that Anurag sent:

1. HTML <title> tag should contain name of object (Community, Collection, Item), instead of just giving the site name
2. Abstracts should be displayed on item view page.
3. citation_pdf_url should be set. For now, it could link to first file, but ideally it'd follow this logic:
   • If an Item has only one file (i.e. bitstream), link to it
   • Else If an Item has multiple files, and one is specified as the "primary bitstream", link to it
   • Otherwise, just link to the first publicly available file (in the ORIGINAL bundle). Also, if possible, make sure this is one of these recommended formats: PDF, PS, DOC/DOCX, RTF, EPUB (See DS-3127).
4. Cleanup citation_keywords to no longer use dc.type. Just use dc.subject

[artlowel]

2,3 and 4 have been fixed.

1, dynamically setting the title, can't be easily fixed because angular 2's title service doesn't work server side yet to fix it we'd have to write our own, something akin to MetaTagService. Since we've already proven that it can be done (with MetaTagService) I propose we simply wait for the angular team to implement a TitleService that works server-side in this case.