Option for mousewheel smooth scrolling

[developer1105]

I would like to suggest an option for smooth scrolling on the file pane. The current scrolling on qtfm reminds me of the scrolling on pcmanfm-qt. It has large steps. The smooth scrolling I wish I could have the option to select is the smooth scrolling which exists in pcmanfm.

This kind of mousewheel scrolling is the reason why I prefer pcmanfm rather than pcmanfm-qt, even though pcmanfm-qt looks somehow more modern. I guess the pcmanfm's smooth scrolling has exactly half the size of the pcmanfm-qt's scrolling step.