Line painting with the terraforming tool

[L3mmy]

In the game, there is currently a way to *terraform* the terrain with a line (Hold Ctrl when using the terraforming tool to make a line) but there this feature is *only working when rainsing/lowering land* and not when painting the grass/walls.
My idea is to make the Line fonctionality work when using painting with the terraforming tool 

[jensj12]

You can only paint full tiles, so it would not make sense to only paint a single edge. Painting a single edge can only be made possible after the new save format is in place.