TypeError when using filters in get_report

```
python my_file.py 
Traceback (most recent call last):
  File "my_file.py", line 18, in <module>
    parser = salesforce_reporting.ReportParser(report)
  File "/usr/local/lib/python2.7/dist-packages/salesforce_reporting/parsers.py", line 11, in __init__
    self.type = self.data["reportMetadata"]["reportFormat"]
TypeError: list indices must be integers, not str

```