Implements assetUrl function to get the image working for Themes

[jor3l]

I think this is better, will return the full url with Themes support. BTW, had to add a beforeFilter and allow access to all in order to use the plugin with Auth component enabled.

[vishal-logiciel]

Thanks for my first ever pull request.. :)
But unfortunately, when I try your code, it gives error. I used the physical path for the images so that only the images residing on the server can be used with Timthumb. Your solution is using the URL to the file instead of the physical path. Maybe we can implement it as a separate function?
I'll check why your code is giving the issue and will let you know.
Again, thanks for your contribution.

[jor3l]

Hey there, no problem lol, about that I'm aware it uses full urls was thinking the same but Timthumb by default blocks any external URL, anyways I'll try to make it work with the physical path but keep the theme functionality, in my case and setup this is a must since the images often resides inside the theme folder or fall back to the global one.