Fixes by Zioth

[zioth]

• Changed to flex positioning. This drops support for IE 9 and below, but fixes a lot of layout issues in various modes.
• Added width option. This makes it easier to define how the menu should look, since the automatic width determination didn't work well in many situations.
• Added wrap option. Recent changes broke a feature in the documentation, where "left" and "right" caused text to wrap around the menu. Using the "wrap" option re-enables this feature.
• Added valign option, which can be "top," "bottom" or "center." It positions the image relative to the text. Default is "top," to match current behavior.
• Menu now works with templates that don't have a hard-coded 42em width.
• A couple other minor bug fixes.

Tested with center, left and menubar.

[zioth]

Added valign option, which can be "top," "bottom" or "center." It positions the image relative to the text. Default is "top," to match current behavior.