catch a reason to crash on startup

[RafiKueng]

Added catch of AttributeError caused by try to read old format on loading .spyderproject files when actually is loading new format project file.

fixes #1845

[ccordoba12]

Thanks a lot for your PR. Seems simple enough, so I'm merging it :-)

[RafiKueng]

well, to be honest, I just applied the patch someone else posted on the google code site.
I didn't find out where the bug comes from, but the patch does allow a clean startup and the affected projects now load up just fine.
I think it was an issue that a new style .spyderproject file gets loaded using the old way (open(fname, 'U') instead of open(, 'rb'), but I couldn't confirm it, mostly because of lacking knowledge of the code and time to invest..
But if the comments in the code are not missleading, then this should be a proper fix to the problem.

[ccordoba12]

@RafiKueng, thanks for looking into it :-)