Update file.json

First draft of file formats
Update file.json

So we had a type unknown in our test set and we also have bigBed which I am not sure we were going to take, but I think we should likely start with generic bigBed
Update file.json

adding in generic bigBed which I am not certain is a good idea but we have them in the test set and in the edw.  Also adding a few more .as file objects
Update edw_file_mock.json

I found the non-compliant tests
Merge pull request #330 from ENCODE-DCC/1572-file_format_enums

1572 file format enums