We want to avoid Object method collision

By using the alternative name for HTTP Methods we avoid collision with the very important `Object#method` method defined [here](http://www.ruby-doc.org/core-2.1.0/Object.html#method-i-method).

By overloading this method we're removing the ability to do metaprogramming (mainly because MRI hasn't yet made a `__method__` method yet).

Since we change a public API (`HTTP::Request#method` to `HTTP::Request#verb`) this requires either a version bump or deprecation notice until we remove the old method.