Update Odo documentation/code for sqlalchemy_redshift

[RAbraham]

This request combines the work of two authors to update documentation and code to refer to sqlalchemy_redshift

[RAbraham]

@branning I don't know if you get notifications from this PR, but in case you don't, Travis failed on a change made for the travis file commit.

[branning]

It's because Spark 1.4 and 1.5 aren't available any more (they're very old by now). That's not something we changed. You'll notice that all recent Travis runs have the same problem. Not sure there's much we can do in the context of this PR. Odo's automated testing is basically completely broken.

[branning]

@RAbraham it looks like the tests are passing now on other PRs. I think we can give this another try. You'll need to pull in the newest commits to blaze/odo that fixed the tests. If it were me, I'd do this:

• rename the master branch to 'sqlalchemy-redshift'
• git checkout -b master origin master to make a new, updated master branch
• rebase the 'sqlalchemy-redshift' branch on master
• push the 'sqlalchemy-redshift' branch to RAbraham/odo
• change the target branch of the pull request from master to sqlalchemy-redshift

After changing the target branch, the PR should update automatically. I believe Travis will start again at that point, and we can see if we can get this PR green! 🍏

[llllllllll]

We changed how we setup travis so that we don't have this spark issue again. Instead of putting this in the conda call in the .travis file can you move this into a new install target like etc/requirments_redshift.txt and then add redshift to the list in extras_require in setup.py. You will also want to put the strictly equals version in requirements_ci.txt This is so that we call all reproduce the versions installed when running the automated tests.