Use sceditors toolbarContainer option to make editor textarea more consi...

Editor textarea height is much smaller on mobile because editor_height includes the toolbar which takes more vertical space on a narrow screen.  By using the toolbarContainer option of sceditor we can avoid this.  Now the text area is much closer to the value set in editor_context['height'].   The various margins, padding, and the grip size are still subtracted but at least those are consistent at different screen widths.

Signed-off-by: scripple <github@scripple.org>