New Features: Switch for Checkbox & Timeline

[Wikiki]

Add sass rules to display checkboxes as switches just by adding “switch” class. issue #538

HTML code:

<label class="switch">
    <input type="checkbox">
    <span>Label</span>
</label>

Add Timeline component : issue #422

[robin900]

@Wikiki Would you be willing to submit this PR as two separate PRs, one for the switch issue and one for the timeline component. I suggest this because I think the switch code will pass muster and get approved much more quickly. The timeline component likely needs additions to the documentation to illustrate its usage and provide a local testbed for the timeline styles; and that will likely take some time to write.

[Wikiki]

Hi @robin900 ,

I're right. But How can I split it in two PRs ? It's the first time a do a PR for an open source project and it's not clear to me.

Thanks

[yo7]

Make commits for each feature then do a PR one by one.