feature: hypothesis included within all group

[8ball030]

Subject of the issue

Describe your issue here. When installing from a python package manager, at present, hypothesis is not included within the [all] group so you have to install it manually :'(

Your environment

• OS: [e.g. iOS]
• Python version: [e.g. 3.7.2]
• Package Version [e.g. 0.1.3]
• Anything else you consider helpful.

Steps to reproduce

Tell us how to reproduce this issue.

Expected behaviour

Tell us what should happen

Actual behaviour

Tell us what happens instead

[DavidMinarsch]

What's the argument for including it @8ball030 ?