Added the collapsing/expanding box for the Provenance data, and also handlers for line-group and line.

Long meeting with PAB during which we discovered that her schema is somehow borked, and validation hasn't been working for her for ages; so there are hundreds of markup errors in the files, such as duplicate xml:id attributes, attributes used in the wrong places, and others. Tried to fix some of them mechanically, but the duplicate ids prevent the XSLT processor from building a proper DOM, so it can't work properly. However, most are the same small number of errors, so they'll be easy to fix.

Still no word from sysadmin with regard to the character encoding issue on Pear.