Extraneous file cleanup
Exportable table view improvements

Added a "preview" json file (small, limited set of records) to allow
table preview of huge datasets without memory problems. Also fixed some
styling issues.
XPATH improvements for XHTML in Document ArchaeoML

Better handling of XHTML in the "internalDocument" element of the
ArchaeoML
Beginning refactored XML document management

Starting to consolidate all XML documents, version control repository
references, update, view count, etc. into a consolidated set of tables.
Also beginning to compress XML documents for better disk use and faster
retrieval.