[Developers] New landing page when updating scripts

I realize sometimes after updating a script the website loading times can be quite awhile. I can't really do anything about the load times but I can make the wait time more bearable by giving you guys some idea of what's going on, so I did. If your script has a lot of subscribers and might take awhile to finish completing, you'll get a little message informing you that it might take a little bit of time. I think this will be better than just staring at the loading image in our browsers.