Add a function to help with recursion

[dhhagan]

make it easier to recursively grab all data if there is more than 1 page..

[biggydbs]

I would like to solve this issue.

[dhhagan]

@biggydbs Awesome! Let me know if you need any help or have any questions.

[biggydbs]

Yes, I tried to run all the tests, but some failed (tests.openaq_test.SetupTestCase -> test_pandasize)

[dhhagan]

That's associated with the pandasize decorator that converts the output to a Pandas DataFrame. The solution should probably be able to deal with both (or I can change the decorator).

[dhhagan]

Hey @biggydbs I just fixed some issues associated with the pandasize decorator; apparently some breaking changes were made to the OpenAQ API that I wasn't aware of (the API calls started failing when keyword arguments were sent that weren't allowed, whereas previously they were silently dropped). I will be merging those changes into master later today (currently are on branch dev-pc); I would love for you to merge in your changes if that was the only issue!