Improve README for new users

[shopify]

Improve README for new users

[marutypes]

Atm in the repo redis performs two primary functions

• stores session information
• stores shop data as one of the shopStore strategy options.

The goal is to add a sql strategy for data storage and use it as the default instead of redis (#30) before we launch.

[AWaselnuk]

@TheMallen Can you please explain the use case for Redis? What exactly are we storing there? We will need to make it clear for partners in the README, or find a way to remove the dependency.

[AWaselnuk]

Another docs idea: I would love to add code comments throughout the key sections of the app that explain some of the Redux architecture as well as other things. Similar to how Rails does it when you run a generator or rails new.