Various integration fixes

[DullReferenceException]

Fixed some integration tests that were causing Travis build failures and local build failures on a Windows box:

• Added sorting to columns before verifying to resolve issues where ordering can differ with different database versions
• Fixed issue where the stack for ORMError objects was undefined
• Fixed "done called multiple times" issue
• Fixed test that was failing for the redshift driver
• Fixed test that intermittently fails for sqlite due to race conditions with in-memory driver
• Increased timeout for a few test setups that were intermittently failing

[dxg]

Looks good, thanks!