[suggest] Add an option "Mouse double-click only" in pref-fillSelectedText

[yfdyh000]

I relayed a user's proposal, he hope that "fillSelectedText" occurs only when using the mouse double-click to select a word, I think it sounds good.

[Quicksaver]

It's not impossible, I'll look into it. But realistically speaking there's a lot more things that will be ahead of this so don't hold your breadth.

[langren1353]

55555555 I think this won't be hard..And I really need this feature while i am just a green hand, so still Hoping......O__O