Filter Charts By Clicking Legend Item

[mrblueblue]

User story

As a user, I would like to be able to click on a legend item to remove data from the chart for that legend item, so I can quickly show/hide some data series. Clicking on the same legend item again would add back the data.

Acceptance criteria

• All chart types should work the same
• Multiple data series could be toggled at the same time
• User should not be able to toggle a series when there's only one
• The line should be hidden. As a stretch goal, line should be greyed-out on legend item hover
• The y axis domain should change to the new data extent if it's not locked
• It should also work with continuous legend
• An event should be triggered that could be used to set a filter on other charts and to persist the show/hide state