ENH: Provide better output if test fails

This test fails on some platforms when the regression and test files
do not match. This patch prints the contents of the two files if they
differ.

Change-Id: Iee6e2c5daffefc654aed405a0585fcf2c71bca1e
Merge topic 'FailingTest_SQLiteTableReadWrite' into master

09adff42 ENH: Provide better output if test fails