Watch themes after activation instead of loading

src/atom.coffee

@@ -54,7 +54,7 @@ class Atom
     @__defineGetter__ 'packageStates', => @packages.packageStates
     @__defineSetter__ 'packageStates', (packageStates) => @packages.packageStates = packageStates
 
-    @subscribe @packages, 'loaded', => @watchThemes()
+    @subscribe @packages, 'activated', => @watchThemes()
     @themes = new ThemeManager(@packages)
     @contextMenu = new ContextMenuManager(devMode)
     @menu = new MenuManager()

src/package-manager.coffee

@@ -63,6 +63,7 @@ class PackageManager
     for [activator, types] in @packageActivators
       packages = @getLoadedPackagesForTypes(types)
       activator.activatePackages(packages)
+    @emit 'activated'
 
   # Public: another type of package manager can handle other package types.
   # See ThemeManager