Add Vagrantfile and Chef recipes to setup development environment for Purpose.

See comments at the top of Vagrantfile for usage. Summary:

   Install VirtualBox and vagrant (vagrantup.com).
   - Tested with vagrant 1.1.5 and VB 4.2.10
   vagrant up  (...wait while stuff happens...)
   vagrant ssh
   cd /platform
   foreman start -f Platform.dev
   Visit localhost:5000 in your web browser.
Allow user specific additions to .env

If you create a env.local file it will be appended to the .env created
by the Vagrant recipe. env.local is in the .gitignore
[john] - added AGPLv3 license
Merge pull request #1 from fightforthefuture/wip-vagrant-chef

Vagrant/chef configuration for a development environment
[NicoPaez] Configuration updated for TravisCI
Turn on SSL for SMTP, use correct sendgrid domain
Speed up page load time in development.

I find page load takes > 1 minute without this, so I'm enabling it by default for FFtF's fork.
[diego] - Updated share counts API endpoint to depend on action page and use ID provided in the URL
Travis configuration updated
Travis configuration updated
[NicoPaez] Travis config updated with xvfb start
[diego] - Remove 'id' from URL for donation get route
Merge remote-tracking branch 'private_platform/polish_api' into develop
[NicoPaez] Travis configuration updated
[NicoPaez] Travis updated to run ALL cucucumber tests
[NicoPaez] Travis configuration split
[NicoPaez] - Rakefile fixed
[NicoPaez] Travis config matrix updated
[NicoPaez] Cucumber test split in groups
[NicoPaez] Bug fix in rakefile