add "problems=problems" as an argument of schedule.Validate ().

[kuwayamamasayuki]

I wrote an extension. At that time, I implemented my own Schedule class in the form of inheriting transitfeed.Schedule.

Then, some warnings were output to the console instead of the HTML file.

The causes of such events are as follows.
In line 592 of feedvalidator.py, schedule.Validate () does not pass the "problems" variable as an argument, so "problems = self.problem_reporter" is executed at line 1336 of the called schedule.py , "problems" variable had been overwritten.

Therefore, I propose to add "problems=problems" as an argument of schedule.Validate ().

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[kuwayamamasayuki]

I signed it!

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[jarondl]

Thank you! this looks correct.