Travis: Use pre-installed gdal in shared OSX build
Travis: Use pre-installed gdal in shared OSX build

naturalatlas/node-gdal,naturalatlas/node-gdal,jdesboeufs/node-gdal,naturalatlas/node-gdal,jdesboeufs/node-gdal,jdesboeufs/node-gdal,jdesboeufs/node-gdal,naturalatlas/node-gdal