Pine tree, pine needles, pine saplng and pine wood nodes, stairs and slabs

![screenshot_2024655708](https://cloud.githubusercontent.com/assets/3686677/4894770/d8b4efc8-63d9-11e4-8492-603c450b97fc.png)


Adds the remaining snow biome nodes from Splizard's snow mod: needles and pine sapling (with permission), plus my own pinetree and pinewood nodes and textures. The pine sapling does not grow into a pine yet, the ABM and pinetree design can be a later commit.
These nodes enable 2 new biomes temperate coniferous forest and taiga, the needles node can be used for many types of conifer, the golden wood planks are good for Scandinavian furniture.
They are needed for mgv5 and mgv7 default biomes, and finally make snow biomes default, as a balance to the hot biomes of deserts and jungles and a suitable reference to the game's Finnish origin.