#1225 Enhance identification of invalid HTML in notes

[Ahasuerus]

Enhance identification of invalid HTML in notes. At this time post-submission warnings do not catch:

1. missing "" in hyperlinks
2. missing quotes around the href parameter

The nightly report aparently catches missing quotes, but not missing "". See http://www.isfdb.org/cgi-bin/view_submission.cgi?4046272 for an example of a submitted bad Note.