upgrade to pyarrow 0.4 (#110)
upgrade to pyarrow 0.4 (#110)

Upgrade CI to pyarrow 0.4
quiltdata/quilt,quiltdata/quilt,quiltdata/quilt,quiltdata/quilt,quiltdata/quilt-compiler,quiltdata/quilt-compiler,quiltdata/quilt-compiler,quiltdata/quilt,quiltdata/quilt-compiler