Polish code editor

[jasmussen]

We've neglected this piece for a while, because we know there will be likely be some CodeMirror involved.

But that's no reason not to make small improvements in the meantime. This PR:

• Removes the dummy quicktag buttons that did nothing.
• Shows outlines around the title and body always.
• Fix a typo that caused the textarea to be small.
• Unify the paddings.
• Relax the lineheight.

Screenshots:

[youknowriad]

Do you think we should try to use the same width and padding/margin as the visual editor, that way when we switch between modes, the title would keep its position?

Also, wondering about the reason to always show the border instead of showing it on focus for instance?

[jasmussen]

Both good questions.

Do you think we should try to use the same width and padding/margin as the visual editor, that way when we switch between modes, the title would keep its position?

Yes. But right now the code editor uses some hacks center it, those hacks are related to the full-wide tweaks. But it's a tangle of code that I'm actually going to try and look at now, separately. Once it's good in the main editor, I'll port the width to the code editor, but I'd prefer doing it later, if it's okay with you.

Also, wondering about the reason to always show the border instead of showing it on focus for instance?

The visual editor is not a form, it's more of a canvas. But the code editor is more like a form, which makes it feel more right to show the outlines all the time.

[youknowriad]

👍