New blocks, improved terrain generation

Hello again, so whats new in this build:

1. Added grass block. It is always generated on top of terrain. Later I will add grass growing (when dirt exposed to sun) and grass decay when something is build on top of it.
2. Added stone block. Now with stone is filled gaps in terrain, later I will improve terrain generation and stone will be found more deeply.
3. Tweaked generated terrain. Now its all filled without gaps. Gaps will be added later when cave will be introduced.

I think I will tell more about what game is about. Adventure of Stickman is sandbox style game, where your live in never ending, randomly generated world. For survival you must find food and gathering various resources for crafting tools and building shelter. It will feature all kinds of different creatures, resources and crafting patterns. Now I will work in user interface. User will be able to choose what block to build, see his inventory, his life and hunger meter.