Publication state support for fetching draft content

[cempesket]

• publication state added to config
• publication state added to api params
• readme updated

[RobinSJames]

Please add this feature - this is exactly what I need to allow previews via webhooks.

[RobinSJames]

Simple yet perfect 👍
local changes work for me.

[dvakatsiienko]

I need this also! Push the PR

[olddustysocksunderthecouch]

Awesome work!

[jestapinski]

Can we get this in and built? Looking to use this feature soon if possible

[remidej]

Thank you for your contribution 🙂

Unfortunately I won't merge it, because we have accepted another PR that provides that functionality with a bit more flexibility: #193. It allows you to set any query string you want for each content type.

I have opened #217 to add an example to the docs of how draft & publish works. But the good news is that with the new v1, you can already use this to fetch draft content