Added fileio.BioPythonFile as a method to parse unknown file formats [closes #106] Biopython can parse more formats than EMBOSS, but surprisingly, it cannot do msf. Also, there is no way to see in the current tests, where a test used biopython or emboss for a particular IO task. This will likely be fixed with the 1.5.0 release with the new fileio system. For now, Biopython has precedence over EMBOSS, so an IO test of msf tests EMBOSS, and IO test of Stockholm tests Biopython.