Add /dynmap sendtoweb command, and published API for sending web messages

src/main/java/org/dynmap/DynmapAPI.java

@@ -0,0 +1,32 @@
+package org.dynmap;
+
+import org.dynmap.markers.MarkerAPI;
+
+/**
+ * This is the interface representing the published API for the Dynmap plugin.  Public methods of the
+ * DynmapPlugin class that are not defined in this interface are subject to change without notice, so
+ * be careful with forming dependencies beyond these.  Plugins accessing dynmap 0.24 or later should
+ * do so by casting the Plugin to this interface.
+ * 
+ */
+public interface DynmapAPI {
+    /**
+     * This method can return null if the 'markers' component has not been configured - 
+     * a warning message will be issued to the server.log in this event.
+     * 
+     * @return MarkerAPI, or null if not configured
+     */
+    public MarkerAPI getMarkerAPI();
+    /**
+     * Test if the marker API has been initialized yet
+     *
+     * @return true if it has been initialized
+     */
+    public boolean markerAPIInitialized();
+    /**
+     * Send generic message to all web users
+     * @param sender - label for sender of message ("Message from <plugin>:") - if null, no from notice
+     * @param msg - message to be sent
+     */
+    public boolean sendBroadcastToWeb(String sender, String msg);
+}