Clean up the code, add docstrings, and get rid of the poorly implemented async client

[wojcikstefan]

Right now the async client makes the code more complex and doesn't really add much value. I doubt it's used in the wild and if it is, then the usage is probably quite confusing and hacky. I think we might as well get rid of it.

Examples of current confusing behavor:

• api.get/post/put/delete is still synchronous
• api.map expects a list of grequests.AsyncRequest, but there's no easy way to construct them.

This PR introduces breaking changes and should be published along with a major version bump.

TODO:

• Add mocked unit tests
• Bump version to v1.0
• Add a GitHub Release and publish on PyPI

[wojcikstefan]

Bonus point against async code - due to monkey patching upon import, grequests can cause warnings/bugs that might be very hard to find. See:

• Removes subprocess monkey patching spyoungtech/grequests#98
• grequests + multiprocessing "resource not found" spyoungtech/grequests#100
• use grequests in Flask with strange error spyoungtech/grequests#99
• Multiprocessing and queue broken by monkey.patch_all(...) spyoungtech/grequests#97
• Importing grequests crashes Python 3.5.1 on OS X 10.11 spyoungtech/grequests#88
• RuntimeWarning due to monkey patching with gevent 1.1.0 spyoungtech/grequests#86

[thomasst]

Looks good (but didn't test).

[wojcikstefan]

@closeio/engineering I believe that once we add unit tests to this PR, we can release it as v1.0. Agreed?

[philfreo]

👍

[thomasst]

Sounds good. So what's happening to async? Are there any plans for it?

[wojcikstefan]

Given the arguments I laid out in #78 (comment) and in the description for #79, I think it might make sense to drop it altogether. This way we maintain a simple & readable helper library w/o any quirks while the users can choose to run multiple concurrent api.get/post/put/delete requests via threading, multiprocessing, concurrent.futures, gevent, etc. depending on their specific use case and environment.

[philfreo]

You can probably remove grequests etc now from setup.py and requirements.txt

[wojcikstefan]

Thanks, done in 02bad5b

[philfreo]

@wojcikstefan Let's move forward with merging this? Can you handle conflicts and publish?

[wojcikstefan]

@thomasst @jkemp101 @philfreo This should be ready to go, please review. If you give the go ahead, I'll merge the changes, bump up the version, create a new release, and deploy to PyPI.