RichText hyperlinks: return as strings, like Qt and GTK do.

Like the other implementations, use YMenuEvent.id instead of
YMenuEvent.item to return the activated hyperlink.

Fixes #30 ( https://github.com/libyui/libyui-ncurses/issues/30 )
version + changelog
Merge pull request #31 from libyui/richtext-event

RichText hyperlinks: return as strings, like Qt and GTK do.