Adds docs and tests for onclick component

[cameronnorman]

Issue #56: onclick Docs and tests

Changes

• Adds tests for onclick component
• Adds docs for onclick component

Notes

• Just explained a simple async function with emitting an event onclick

[jonasjabari]

Onclick, not Action ;)

[jonasjabari]

1. The onclick only requires emit. data is optional
2. The usecase you describe sounds pretty complicated. The main purpose of this component is to provide an easy to use client side event emitting API. Normally it would only wrap one component, which shows an interaction element such as one button or one specially styled div or something

onclick emit: "my_event" do
    button text: "click"
end
async rerender_on: "my_event" do
    #some content which gets rerendered onclick
end

3. If you want to show the more advanced usage of onclick including data param usages and a separate method defining the config of the onclick component, please use a second example and increase the complexity of your examples step by step. Otherwise you may "overwhelm" new matestack users
4. please add a separate section where you explain which params could be used for the onclick component. We use this approach in other component documentations as well :)

[jonasjabari]

I think this is a bit misleading: the ruby method run_this_function just returns a config hash, which determines the client side behavior of the onclick component. I would rather call the ruby method onclick_config although it sounds not as nice as yours. I just don't want to confuse the reader.