Hotfix v0.38.2 - Walk speed, bugs

Another quick update that re-adds the faster walk speed when walking on Pavement tiles.  If a Pavement tile is under a Habitat Module, it still applies a walk-speed bonus.

Also fixed a few inventory bugs where the game would crash if you had a single item in your inventory, placed it into a Generator (or Water Supply), then clicked on the Generator again with nothing equipped.