Pause/Unpause building option for the pause tool.

Often you place a blueprint, and want it to start build, but due to population/power etc you dont want the building to start working when built.
So having a "shift" option or something on the pause tool that would only Unpause/Pause the building, so you can differ between toggling construction and the pause of the building.
Currently for my blueprints, it makes me go mark all the pipes/belts and so unpaused to get constructed and then "Unity" building the buildings i need active.