increase MAX_REQNUM_SIZE consistent with change to request_number col SIGNED -> UNSIGNED

major upgrade - app uses vep api_version to look for available cache types (ensembl, refseq, merged) and disables any from selection if not available; results page displays api version and selected cache database; vep wrapper captures vep.pl stderr for display on results page; added vcf 'filter' col to results page; enabled HGVS notation function

new vcf analysis section; moved ChartMaker to NGS::ChartMaker