Adjustable tooltip widths (also for non-rich-text tooltips)

Currently the width of tooltip windows isn't adjustable. Additionally the default width is too low (from my point of view).

Please make the width of tooltips adjustable so it wraps words according to that width.

A related issue is that non-rich-text tooltips are not word-wrapped at all. This can be pretty painful especially for verbose translations. If possible also enable wrapping for non-rich-text tooltips so programmers do not need a wrapper function that must be added to every setTooltip() call to achieve the same sensible behaviour.