Add block.getRelative() funcs and docs (#3)

Minecraft.Server.FourKit/Block/Block.cs

@@ -121,4 +121,46 @@ public class Block
             return NativeBridge.BreakBlock(_world.getDimensionId(), _x, _y, _z) != 0;
         return false;
     }
+
+    /// <summary>
+    /// Gets the block at the given offsets
+    /// </summary>
+    /// <param name="modX">X offset</param>
+    /// <param name="modY">Y offset</param>
+    /// <param name="modZ">Z offset</param>
+    /// <returns>Block at the given offsets</returns>
+    public Block getRelative(int modX, int modY, int modZ)
+    {
+        return getWorld().getBlockAt(getX() + modX, getY() + modY, getZ() + modZ);
+    }
+
+    /// <summary>
+    /// Gets the block at the given face
+    /// <para>This method is equal to getRelative(face, 1)</para>
+    /// </summary>
+    /// <param name="face">BlockFace to get relative to</param>
+    /// <returns>Block at the given face</returns>
+    public Block getRelative(BlockFace face)
+    {
+        return getRelative(face, 1);
+    }
+
+    /// <summary>
+    /// Gets the block at the given distance of the given face
+    /// <para>For example, the following method places water at 100,102,100; two
+    /// blocks above 100,100,100.</para>
+    /// <code>
+    /// Block block = world.getBlockAt(100, 100, 100);
+    /// Block shower = block.getRelative(BlockFace.UP, 2);
+    /// shower.setType(Material.WATER);
+    /// </code>
+    /// </summary>
+    /// <param name="face">BlockFace to get relative to</param>
+    /// <param name="distance">Distance to get relative to</param>
+    /// <returns>Block at the given distance of the given face</returns>
+    public Block getRelative(BlockFace face, int distance)
+    {
+        return getRelative(face.getModX() * distance, face.getModY() * distance, face.getModZ() * distance);
+    }
+    
 }