Reduce font size and margin of asset editor headers

In order to try to reclaim a bit of veritical space in the asset
editor, make the font the same as that of an h4 element and get
rid of the top/bottom margins.

Addresses #846
Make sure body textarea is visible on edit

Make sure the ``body`` field's textarea element is visible when
editing a text asset before initializing the rich text editor.

This is needed because the wysihtml5 editor hides the textarea
by setting it's display property to ``none`` when it is initialized.
However, if the user clicks the "Cancel" button, the editor never
unhides the textarea element before the editor is destroyed.

The next time an editor is initialized, it copies the CSS properties
from the textarea, causing the editor to be hidden erroneously.
Don't load debugging version of Google Analytics script

It really clutters up the debugging output in the console.  This
can be edited when needed in development and doesn't need to be
always loaded, even in debug mode.