Bibliography changes
Added explicit citations
Changed image sizes
big data > Big Data
texttt formatting
some relevant (SKA) figures …  are listed below
latest pdf
Change quotation style
Change from quotation to italics (classical)
Added UML citation
Added URLs to TAP clients
Added query types
Added citation for PQL
Better sectioning and section labels
typos
Section label changes
Moved FITS before ObsTAP
Changed explanation of ObsTAP
Added UWS recommendation citation
Reorganisation of vo.tex