Update the npapi plugin to support OSX. Also, adds a proper make crx step.

Review at http://gwt-code-reviews.appspot.com/1036801


git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@9128 8db76d5a-ed1c-0410-87a9-c151d255dfc7
diff --git a/plugins/npapi/manifest-template.json b/plugins/npapi/manifest-template.json
index d54ddd8..ecf565f 100644
--- a/plugins/npapi/manifest-template.json
+++ b/plugins/npapi/manifest-template.json
@@ -20,6 +20,7 @@
   "plugins": [
     { "path": "WINNT_x86-msvc/npGwtDevPlugin.dll", "public": true },
     { "path": "Linux_x86-gcc3/libGwtDevPlugin.so", "public": true },
-    { "path": "Linux_x86_64-gcc3/libGwtDevPlugin.so", "public": true }
+    { "path": "Linux_x86_64-gcc3/libGwtDevPlugin.so", "public": true },
+    { "path": "Darwin-gcc3/gwtDev.plugin", "public": true }
   ]
 }