Finish off event detail page

[chrisdevereux]

The current event detail page (https://accelerate-staging.herokuapp.com/event?id=9e4d0f3c-5b1b-483f-92d1-3c0864176abf) doesn't match the wireframe (https://balsamiq.cloud/ssqd6/pd0rd/r2278).

It needs finishing off.

Acceptance criteria:

• Should display all information listed in the wireframe
• Should embed a map showing the location of the event.

There are some fairly easy to use react components wrapping google maps, such as https://github.com/tomchentw/react-google-maps.