Update gitignore and mapmerge for tgstyle maptree

This commit updates the .gitignore file to ignore the proper files with
the new tree system, and modifies the mapmerge files to the latest -tg-
files, as those are already compatible and written for the new tree
system.

tools/mapmerge/Source/SavingThread.java

@@ -0,0 +1,37 @@
+class SavingThread extends Thread
+{
+  int z;
+  Map mymap;
+  boolean done;
+  int progress;
+  StringBuilder result;
+
+  public SavingThread(int paramInt1, Map paramMap, int paramInt2)
+  {
+    this.z = paramInt1;
+    this.mymap = paramMap;
+    this.progress = 0;
+    this.done = false;
+    this.result = new StringBuilder(paramInt2);
+  }
+
+  public void run()
+  {
+    this.result.append("(" + this.mymap.minx + "," + this.mymap.miny + "," + this.z + ") = {\"\r\n");
+
+    int i = (this.mymap.maxx - this.mymap.minx) * (this.mymap.maxy - this.mymap.miny) / 100;
+    int j = 0;
+    for (int k = this.mymap.miny; k <= this.mymap.maxy; k++)
+    {
+      for (int m = this.mymap.minx; m <= this.mymap.maxx; m++)
+      {
+        this.result.append(this.mymap.getIdFor(this.mymap.contentAt(m, k, this.z)));
+        j++; if (j >= i) { j = 0; this.progress += 1; }
+      }
+      this.result.append("\r\n");
+    }
+    this.result.append("\"}\r\n");
+    this.result.append("\r\n");
+    this.done = true;
+  }
+}