Back again!

This time I only worked on fixing two stubborn bugs (There might be some bug with the devlog time being too much. I will check and ask support if any).

Bug #1: Layer reordering does not account for expanded layers

Previously, my logic was

initial_layer_index = floor(mouse_pos / layer_height
target_layer_index = round(mouse_pos / layer_height

since layer_height is the height of an unexpanded layer, the program thinks I’m moving the wrong layer to the wrong place.

Bug #2: layer reordering does not reflect correctly in the layers_ vector.

I keep forgetting that the last layer added to a vector is appended to the end, but is drawn on top of other layers. The problem was in the logic of std::rotate (had to brush up on STL for that). It caused a lot of inconsistency and crashs when reordering layers, especially when I fixed bug 1.