Create info "tidbit" component

[mikelbrierly]

User Story:

As a User,
I want to be gently guided through parts of the site to get an understanding of how they work,
So that I can easily get up to speed with the Halogen tool

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Acceptance Criteria:

We want to create a component that is somewhere between a notification and a modal. We'll call it a tidbit, and it should be dismissable, and able to contain any amount of text. It should also have the blurred glass background effect as per the mocks.

• Create a new tidbit component
• The component should accept input text, and should have the blurred glass background effect
• The component should have an "i" icon in the top left
• You should be able to dismiss the tidbit