test for axis dates in README
test for axis dates in README

dpattermann-usgs/gsplot,jread-usgs/gsplot,jread-usgs/gsplot,ldecicco-USGS/gsplot,lindsaycarr/gsplot,lindsaycarr/gsplot,USGS-R/gsplot,ldecicco-USGS/gsplot,dpattermann-usgs/gsplot