Fix incorrect  cd added to .profile in Vagrant provisioning.

Now you should be able to after `vagrant up`:
`vagrant ssh`
`make run`
This works correctly now.
Add a Dockerfile to build a gittip container
Added documentation for using Docker
Rename the `memberships` table to `takes`; #2282

`memberships` was a bad name for this table because it's ambiguous with
community memberships. Renaming to `takes` fits the usage we've arrived
at and is parallel to `tips`. Tips and takes! Membership is then an
emergent property of data recorded in the takes table.
Add pyinvoke and convert paypal email setup script to invoke task.
Modify Vagrantfile to use a custom gittip image.

The use case for this change is to allow multiple new devs to
easily set up clean new dev environments over a slow or non-existent
network. (This actually happened at Pycon 2014). The instructions for
creating this image have been added as comments in the readme file, and
quick start instructions have been added to the readme file. The online
URL for the image is http://downloads.gittipllc.netdna-cdn.com/gittip.box
Move production envvar loading into pre-task.
Fix regression in error tester
Greatly simplify error.html

This is supposed to be a stub for testing error handling. It doesn't
need to be overly complex.
Teach masspay.py to use new paypal_fee_cap field

Rel. #1675
Change a flag to fit my brain better

I always try masspay.py -p, and the user is always right! :-)
Drop interactive CLI entirely

I never use it. Instead let's just point to the command line switches.
Here's a report to help with escrow balancing

Over on #1988 I've done some more thinking about how to manage our
escrow across our multiple accounts. This adds a report to the masspay
script to help make decisions about that.
Better PayPal penny testing
Add images needed for Balanced Payments sections
Merge pull request #2283 from aisipos/vagrant_base

Vagrant base
Merge branch 'master' of https://github.com/gittip/www.gittip.com into dockerfile

* 'master' of https://github.com/gittip/www.gittip.com:
  Modify Vagrantfile to use a custom gittip image.
  Keep manual exchanges out of payday self-check
  Append index to schema.sql; #1417
  Fix incorrect  cd added to .profile in Vagrant provisioning.
  Give devs a little pointer re: branch.sql
  Remove os.environ from error handling test page

Conflicts:
	README.md
Added Docker instructions to the Quick Start section
Fixed link to Docker usage
Merge pull request #2288 from citruspi/dockerfile

Dockerfile