Fixed the loading order of an app's dependencies.
If we load apps first, libraries won't be there, hence throwing
exceptions at run time.
For example, this can be reproduced with any library that needs to be registered like ScssInitialiazer.
See #1448#issuecomment-26143346

Apps not being loaded at the last point makes things like libraries
Added @ujifgc's suggestion #1449#issuecomment-26145420 to launch the circular loader.
Merge pull request #1449 from padrino/fix-loading-order

Fixed the loading order of an app's dependencies.