Figure out how to run recipes on intervals over time

[ahal]

Right now, you can run a recipe once to retrieve a single "data point". For example, you might run:

adr backout_rate --from today-week

to get the backout rate over the past week. But if you want to see how the backout rate is changing from week to week, you have to run the recipe multiple times (with different date arguments).

I want to make it easier for people to run existing queries over time. There are two options:

1. Do this within the query itself. We can create an "edge" over the time dimension within the actual query. Here is an example of a query that does this: http://54.149.21.8/tools/query.html#query_id=k0CFjwYN

2. Make multiple requests to ActiveData (essentially automate the manual labour of running it multiple times).

The benefit to 1) is that it is less resource intensive on ActiveData. The value of 2) is that it keeps the logic in the recipes (and adr itself) simpler. I'm leaning towards solution 1. This is a pretty major and tricky change. I think we'll want to do some refactoring before we attempt it.

[ahal]

Just a heads up that I won't be accepting contributions for this issue.