(dist) fix version extraction in Makefile
(dist) fix version extraction in Makefile

tomhughes/carto,madeinqc/carto,midnightcomm/carto,CartoDB/carto,CartoDB/carto,stefanklug/carto,clhenrick/carto,gravitystorm/carto,1ec5/carto,pnorman/carto,mapbox/carto,whitelynx/carto