Add explicit pre-req vesions of HTTP::Tiny and Net::SSLeay

We need SSLeay >= 1.49 for https support
We need a recent HTTP::Tiny >= 0.014 for www_form_urlencode()
Documentation fix: list's state option takes a string

The v2 API docs suggests using the strings 'read' and 'unread'
as options to the 'state' parameter. So we'll adjust the synopsis
to show this.
Extend the `pocket` script to list pocket items.

It's super-simple functionality, but it works. :)
README.md clean-up. Updated Makefile.PL for non-dzil users.
Merge pull request #4 from pjf/master

Lots of minor bugfixes and improvements