Provides store method for retrieving traffic usage data based on
period parameter, and UI + ui hook with the new chart for displaying
traffic usage data spread out over selectable month.
In this PR we copied and adapted a plugin written by DX for highlighting
a column in the chart:
There are some minor improvements planned which will come in a separate
PR, reversing the order in legend and tooltip so the colors go from
light to dark, and adding a month -sum below the legend
## Discussion points
- Should any of this be extracted as a separate reusable component?
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Co-authored-by: Nuno Góis <github@nunogois.com>
Adds lazy loading to the network routes, so we end up with smaller
chunks in the build.
Also adds a `start:prod` script that can prove useful to test the chunk
loading behaviour locally.
