add path prefix to exception message.
add path prefix to exception message.

liip/LiipImagineBundle,prolixtechnikos/LiipImagineBundle,liip/LiipImagineBundle,robfrawley/LiipImagineBundle,prolixtechnikos/LiipImagineBundle,prolixtechnikos/LiipImagineBundle,robfrawley/LiipImagineBundle