Rather than accepting a naked string, accept a DeleteCollectionParams
struct so that new optional parameters can be added in the future
without breaking the API.

This adds support for deleting collections.

Resolves #1.

Add NewClientWith constructor

This adds a new constructor to build Clients which operates on a Config
struct rather than positional parameters. This will enable adding new
parameters in the future without breaking the API.

To begin with, this introduces a new URL parameter that wasn't
previously available. An example of another parameter that could be
added in the future is the timeout (to override the default timeout).

Existing constructors have been transitioned to the new one because it
implements a superset of their functionality.

Minor note: The Tor constructor wasn't respecting the default timeout
but with this version, it does.

Resolves #8

Fixes bug introduced when we moved `Token` into the func's parameters,
out of PostParams.

Moves the ID and token params out of PostParams and into the func's
parameters. A currently-unused `collection` parameter is left in for the
future, when the backend supports updating and deleting collection posts
via slug, not post ID.

Previously, they all said the same thing

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Merge tag 'v1.1'

Version 1, with a better README

This uses a local proxy to communicate over Tor. Code is from the
writeas-cli.

removed unreachable code

use correct verb for error formatting

This closes #3