Commits to increase test coverage

[apeckham]

mysql2postgres is awesome. I spent some time increasing test coverage to encourage further development and prevent regressions.

I added tests for:

• enum conversion
• force_truncate (which had a bug and was not being respected)
• printing to stdout
• datetime conversion and datetime column defaults
• foreign keys
• unique indexes and renamed unique indexes
• null conversion

Thank you!

Aaron

[jcoleman]

My newest pull request includes these commits as well. Note all tests do run successfully.

[apeckham]

tardate, would it be better if I submitted this to maxlapshin's branch? I'm not sure where the best place is for these changes.

[jcoleman]

maxlapshin has been rather unresponsive on a few month's worth of pull requests on his repo--it might be beneficial for someone to ask him if he would like someone else to take over managing the primary repo.