#1314 Manager::LoadResource failure does not show file on LocateDataFile(..) failure

[Andrew Cottrell]

The current src/sdk/manager.cpp Manager::LoadResource(const wxString & file) failure if the file does not exists outputs "" for the resource file and as such it is a PITA.

This change is to include the file name passed into the function in the LogError message so that at least you can see while file is failing.

[Miguel Gimenez]

Applied in [r12903], thank you.