Moved placeholder logic out of Javascript and the DOM and into CSS

[izak]

This should help with cursor navigation and serializing the DOM.

Also, titles should be able to load up with markup in them instead of just text.

Original request here: wysiwhat#45

[TomWoodward]

does this actually work? appears to not be supported anywhere according to https://developer.mozilla.org/en-US/docs/Web/CSS/attr

nvm, is supported in all modern browsers

[philschatz]

Yep, this will work with any browser that supports CSS 2.1

[therealmarv]

looks good for me. Notes working in demos 👍

[TomWoodward]

i'm still worried but if you guys have tested and it works then 🍰

[therealmarv]

Do you know how reproduce your error @tmsp1 ?

[TomWoodward]

definitely still getting mapping error when trying to save documents with notes on testing, what environment are you guys using?

you can see that there are a bunch of classes that should be being stripped off note's title elements that aren't <div class="title aloha-editable aloha-block-blocklevel-sortable ui-sortable" placeholder="Add a title (optional)" id="26c6eb17-0d15-5711-b3ce-170947dc7606">My note title</div> the error i'm getting is just the standard TODO: p/@class

[TomWoodward]

@therealmarv @philschatz added a few commits to fix mapping errors, another round of review on this would be awesome