Fixed facing methods for fence gates.
Updated magic values for Skull directions.

Minecraft 1.8 switches the representations of east and west.
Added API for manipulating banners and banner patterns.

Banner blocks have facing, base color, and pattern. Banner patterns are a
list of layers, which have a shape and color.
Merge branch 'master' into pr-34
Merge pull request #1 from dequis/pr-34

Updated your dynamic recipes PR