[Update] Templates Editor update (v1.83) (Patreon)

Quite a small update. Templates Editor are reviewed and that resulted into 2 new editor tools creation: Mask and Invert. The first one allows to automatically lower height of the cells near map edge or, alternatively, lower cells close to map center. Invert just mirrors the heightmap so that now we can make Isthmus template be aligned to both left and right side.

Also I have added a new heightmap template using this new mask tool. It looks very fractal-like, but it does not use any fractals, so it got the name Fractious.

Heightmap template editor guide is also updated, so you can check the actual version.