brtRevisionPtr breaks parsing

[berzniz]

Parsing an xlsb file with brtRevisionPtr breaks with error:

Error: Unexpected record 3073 BrtRevisionPtr

According to https://msdn.microsoft.com/en-us/library/mt793316(v=office.12).aspx - this field should be ignored. When ignoring it (I monkey patched the final javascript file), it works and parses the file correctly.

I can not send the xlsb test file since it has sensitive information. I'm trying to create a blank test file that can be shared.

[SheetJSDev]

Part of why it errors on unrecognized records is to find files with these records! Even if you can't publicly share it, we'd love a small test file