Add focusin and focusout

[patricia-gallardo]

This is my first draft for issue 278

[LJWatson]

This LGTM. Ping @chaals for final review.

[cynthia]

Just as a passing remark - I think the commit message could have been worded/formatted better.

[cynthia]

@chaals suggested I elaborate on how - so here is the list of options.

1. Squash into a single commit and rewrite commit message. (this can be done with the "Squash and merge" button on GH's web UI.)
2. Rebase. (This would be what would happen normally if there was critic available. Unfortunately that isn't the case, but it can be done from the CLI..)

Normally amend would be an option, but with the fixup commit that is a bit harder.

[chaals]

Sangwhan suggested:

Squash into a single commit and rewrite commit message. (this can be done with the "Squash and merge" button on GH's web UI.)

Since I use the Web UI to Squash and merge, I rewrite the messages as relevant. (To the best of my ability...)

We should probably document this in our documentation, but I don't think you should worry about it overmuch for this case.

[chaals]

The technical bit looks good...

Please

• update the changes section to note this
• add relevant acknowledgements
• update the attributes index

[siusin]

The test looks great! \o/

@patricia-gallardo could you update sections/events.include to add the focusin and focusout events as well?

[chaals]

Bruce will work on this on Friday (deadline day for the milestone)

[patricia-gallardo]

Thank you @brucelawson and @chaals for picking this up and finishing it. I still have quite a bit to learn.