Convert biom_validator.py to pyqi

This one's a little strange because the Command accepts a JSON object instead of a parsed BIOM Table. Instead of throwing exceptions (as was previously done), a report is generated by the Command. The user has control over whether the report is detailed or not. The Command also returns a boolean that indicates whether or not the JSON is valid BIOM. The return code of the optparse script is also set to indicate success or failure (in addition to the printed report).