0.3.0 Alpha Released

This fixes a bug involving the rendering of the grass mask, such that it no longer overlaps blocks that it shouldn't.

This also brings a new feature: Tilesets.  Tilesets are a grouping of similar block types that do not display edges over each other and/or that visually connect with each other, forming a seamless whole.

Nearly all of the plating blocks have been visually re-worked to use this new feature, so they will appear somewhat different.  However, they also now have an alternate block that comes in a sloped form.  This  allows  you to build, for example, a pyramid with a sloped exterior, with rooms on the inside that have squared off corners.

Below is an example plastic pyramid, to demonstrate: