add the help (?) button to the menu

[szabgab]

Make it easier for the first-time reader to find the available keyboard shortcuts.

• connect to the help popup trigger code
• add the configuration option to show the help icon
• only set the event listener if the icon is there

[rustbot]

:umbrella: The latest upstream changes (possibly 21f2435182e4a80c0bd0e3184ce36f7a57529d08) made this pull request unmergeable. Please resolve the merge conflicts.

[GuillaumeGomez]

Sounds like a good idea. Why adding an option to disable it though?

[szabgab]

Why not? Some authors might want a "cleaner menu"

[szabgab]

And I am still trying to figure out how to include the svg version of the icon

[GuillaumeGomez]

Why not? Some authors might want a "cleaner menu"

Sure, but then the overall coherency is reduced.

And I am still trying to figure out how to include the svg version of the icon

You can use the one in rustdoc.

[quencs]

rustdoc

[quencs]

rustdoc

[ehuss]

@quencs Please stop.