Inspired by issue 220, I've: * Verified that all hooks listed in the documentation still exist in the codebase. * Verified the parameters for all hooks listed in the docs with the actual parameters in the hook calls in the codebase. * Verified that all hooks in the codebase are listed in the Hooks documentation page, with the exception of the transport.internal.... hooks.

Note: * The hook descriptions for the added hooks can probably use further improvement. I wasn't always sure how best to describe the hook event. * The ordering of this list looks to be a loose "requests hooks, curl hooks, fsockopen hooks and those in the order they are called" order. With some of the additional hooks, it wasn't always clear where to place them within this loose order, so suggestions to improve the order are welcome.

Also note the the naming of the request.progress hook seems inconsistent. I do understand why the hook uses request instead of requests, but this may be something to revisit at a later point in time.