QVX file format
                A QVX formatted file describes a single table followed by the actual table data. The file includes:
- An XML formatted table header (QvxTableHeader) written in UTF-8 character set. The header describes the fields in the table, the layout of the subsequent data together with some other meta-data.
 - 0 byte written at the end of the table header, i.e. directly after </QvxTableHeader>, and before writing the actual data.
 - 
                        
The actual data formatted according to the preceding table header.