new boards menu with custom submenus

https://code.google.com/p/arduino/issues/detail?id=257

app/src/processing/app/tools/MapWithSubkeys.java

@@ -0,0 +1,66 @@
+package processing.app.tools;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Map.Entry;
+
+public class MapWithSubkeys {
+
+  public static MapWithSubkeys createFrom(Map<String, String> input) {
+    if (input == null) {
+      return null;
+    }
+    MapWithSubkeys target = new MapWithSubkeys();
+    for (Entry<String, String> entry : input.entrySet()) {
+      String[] entryParts = entry.getKey().split("\\.");
+      if (entryParts.length == 1) {
+        target.put(entryParts[0], entry.getValue());
+      } else if (entryParts.length == 3) {
+        target.get(entryParts[0]).get(entryParts[1]).put(entryParts[2], entry.getValue());
+      } else if (entryParts.length > 3) {
+        StringBuilder sb = new StringBuilder();
+        for (int i = 3; i < entryParts.length; i++) {
+          sb.append(entryParts[i]).append(".");
+        }
+        sb.deleteCharAt(sb.length() - 1);
+        String key = sb.toString();
+        target.get(entryParts[0]).get(entryParts[1]).get(entryParts[2]).put(key, entry.getValue());
+      }
+    }
+    return target;
+  }
+
+  private final Map<String, String> values;
+  private final Map<String, MapWithSubkeys> maps;
+
+  public MapWithSubkeys() {
+    this.values = new HashMap<String, String>();
+    this.maps = new HashMap<String, MapWithSubkeys>();
+  }
+
+  public Collection<String> getKeys() {
+    return values.keySet();
+  }
+
+  public Map<String, String> getValues() {
+    return values;
+  }
+
+  public String getValueOf(String key) {
+    return values.get(key);
+  }
+
+  public MapWithSubkeys get(String key) {
+    if (!maps.containsKey(key)) {
+      put(key, null);
+      maps.put(key, new MapWithSubkeys());
+    }
+    return maps.get(key);
+  }
+
+  public void put(String key, String value) {
+    values.put(key, value);
+  }
+
+}