Simplify Vagrantfile.
Enforce Unix line endings on Windows.
Show warning in Vagrant to existing Windows contributors.

Since Unix line endings are enforced now, existing Windows contributors
may have cloned the repo with autocrlf set to true and so Vagrant will
not work properly. This warning message gives instructions on how to
fix it. This also prevents confusing CRLF situations in the future.

See
- https://help.github.com/articles/dealing-with-line-endings
- http://adaptivepatchwork.com/2012/03/01/mind-the-end-of-your-line/
- http://git-scm.com/docs/gitattributes
Fix Vagrant dependencies.
Pin Postgres and add TODO to pin the others.
Upgrade fake-factory to 0.3.2.
Use local gittip database by default.
Inline the Postgres version.

I had this separate because we were initially going to
set the "trust" in pg_hba.conf, which requires
knowledge of the version in the path.
Configure Postgres.
Add 'run' script with run instructions.
Update README to say py.test instead of nosetest
Merge branch 'master' into sorta-refactor-elsewhere
Bump version to 11.1.3
Bump version to 11.1.3-dev
Merge pull request #1840 from joeyespo/fix-vagrant

Fix Vagrant
Began adding account linking with Venmo