Add basic transcription previews
Using a basic XSLT stylesheet allows us to provide previews even before we have sent documents to MVD (important at the moment to work around issues with HritServer not being able to process large files). Temporarily disables MVD previews being inserted on resource record pages in repository.js and instead adds a link to the content preview page (which either renders an image, plain text in pre tags or XML via the formats.xsl stylesheet. The XSLT stylesheet comes from the MVDTouch version of COM_MVD (the precursor to HRIT server)