"Extending Twine" suggestion: menu items should be able to have icons

[webbedspace]

I really don't get why this no-icon restriction is necessary - it seems like there's enough room in the menus to fit in an icon alongside the text labels (especially since the labels themselves don't seem to have a length limit), and having icons for commands with a strong visual component (like text styles) seems pretty obviously beneficial.

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[klembot]

The conflict I felt with this is that checkmark icons (for the checked property) are easy to confuse with icons meant to identify the action--they also get lost in the icons in general, I feel. But if there's a strong enough demand for it, we could make icons allowed in menus, though they would have to be mutually exclusive of being checked.