Provide method() accessor on Response & minimum Class::Tiny version.

[FGasper]

Issue #16

[xdg]

Let's separate the two issues. I'm happy to add minimum Class::Tiny. But there's no 'method' attribute on the response object so I don't see a reason to add an accessor.

[FGasper]

Hm … I don’t see what is in my own code that was adding method, but yes, as it’s not there in HTTP::Tiny’s response there’s no reason to add the accessor.

Do you want a separate PR for Class::Tiny?

[xdg]

That's OK. I'll add the Class::Tiny prereq -- it's a trivial change.