[PowerUserHotkey] Allow picking placeable tiles with Q

[eradicator]

Equal to picking buildings with Q (default) i want to pick ground tiles (stone path, concrete, etc) when hovering a placeable tile. This should be a seperate hotkey from the entity picker (default could be Q or <unbound>), because it might be annoying to people who hammer q just to empty their cursor.

(I'd mod it myself, but cursor position......... *sigh*)