GTEx gene-level expression summary for Snaptron

GTEx gene-level expression summary from the Snaptron collection.  Format is a tab-separated text file compressed and indexed using BGZip, along with supplementary files containing a Tabix index for the data (ending in tbi) as well as two files describing the samples represented in the columns of the data file (ending in tsv).  Uses GENCODE v25 annotation for quantification.  Source data for the quantification are the bigWig files produced as part of recount2.  More information at http://snaptron.cs.jhu.edu.