add RavenPlugin interface

ravenjs/ravenjs.d.ts

@@ -58,7 +58,7 @@ interface RavenStatic {
     /** Raven.js version. */
     VERSION: string;
     
-    Plugins: any;
+    Plugins: RavenPlugin[];
 
     /*
      * Allow Raven to be configured as soon as it is loaded
@@ -100,7 +100,7 @@ interface RavenStatic {
      *
      * @return {Raven}
      */
-    addPlugin(plugin: any, ...pluginArgs: any[]): RavenStatic;
+    addPlugin(plugin: RavenPlugin, ...pluginArgs: any[]): RavenStatic;
 
     /*
      * Wrap code within a context so Raven can capture errors
@@ -188,3 +188,7 @@ interface RavenTransportOptions {
     onSuccess: () => void;
     onFailure: () => void;
 }
+
+interface RavenPlugin {
+    (raven: RavenStatic, ...args: any[]): RavenStatic;
+}