SBMLNetwork is a library designed to enable software developers and systems biologists to interact with the graphical representation of SBML (Systems Biology Markup Language) models.
The exception message raised when a model couldn't be loaded properly is modified to help the user understand what was the main reason the model couldn't be loaded in PR #79
When load is given a file name that doesn't exist it should check that the file exists and issue a file not found message if it can't find it.
It should check to see if the string in load is a viable file name before checking, otherwise it can assume its a string.