update deps
latest node-srs@0.4.5
update gdal to 0.3.1 and mapnik to 3.1.1
appveyor: test both vs 2013 and 2014
only 64 bit
Debug arch
try to clear out default node.exe
try to clear out default node.exe part 2
use del
try to work around mapnik/node-mapnik#349 and disable v0.11 due to joyent/node#8527
Merge pull request #45 from mapbox/update-deps

Update node-gdal, node-srs, and node-mapnik to latest releases