These use the example files published in the Apache ORC repository.
Author: Wes McKinney <wesm+git@apache.org>
Author: Antoine Pitrou <antoine@python.org>
Closes#2428 from pitrou/ARROW-1968-orc-tests and squashes the following commits:
6f538923 <Wes McKinney> Update quay.io image used for pandas 0.23.4
28335ff9 <Wes McKinney> Use pandas 0.23.4 everywhere
d5d34e53 <Wes McKinney> Upgrade pandas in manylinux1 image to latest
c51a77f1 <Wes McKinney> Do not use binary read mode
dd456204 <Wes McKinney> Use pandas for ORC tests, delete pickles
43b0208a <Antoine Pitrou> Add decimals test
06c0f5f4 <Antoine Pitrou> Fix tests on py2
42f01864 <Antoine Pitrou> ARROW-1968: Add basic unit tests for ORC reader
