Add world handling (and fall to ground)

- World is now properly parsed and stored from chunk data
- Block changes are also handled and world updated accordingly
- Added ground checking, the player will move down to reach the ground
- Performance tweaking in Protocol18, using lists instead of arrays
- Fix player look not properly skipped causing invalid location after
teleport

MinecraftClient/Mapping/ChunkColumn.cs

@@ -0,0 +1,48 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace MinecraftClient.Mapping
+{
+    /// <summary>
+    /// Represent a column of chunks of terrain in a Minecraft world
+    /// </summary>
+    public class ChunkColumn
+    {
+        public const int ColumnSize = 16;
+
+        /// <summary>
+        /// Blocks contained into the chunk
+        /// </summary>
+        private readonly Chunk[] chunks = new Chunk[ColumnSize];
+
+        /// <summary>
+        /// Get or set the specified chunk column
+        /// </summary>
+        /// <param name="chunkX">ChunkColumn X</param>
+        /// <param name="chunkY">ChunkColumn Y</param>
+        /// <returns>chunk at the given location</returns>
+        public Chunk this[int chunkY]
+        {
+            get
+            {
+                return chunks[chunkY];
+            }
+            set
+            {
+                chunks[chunkY] = value;
+            }
+        }
+
+        /// <summary>
+        /// Get chunk at the specified location
+        /// </summary>
+        /// <param name="location">Location, a modulo will be applied</param>
+        /// <returns>The chunk, or null if not loaded</returns>
+        public Chunk GetChunk(Location location)
+        {
+            return this[location.ChunkY];
+        }
+    }
+}