web2py_filesystem Updates/Corrections

[macneiln]

1. Attempting to store DAL table structure details in the database rather than the filesystem is currently failing due to an encoding typo where the filename is being inadvertently stored as bytes rather than it's filename in one section, which results in that file not being found when it's queried for and thereby attempts to recreate tables that exist and fails as it's violating the web2py_filesystem primary keys.

2. Binary types in PostgreSQL are "BYTEA" but the web2py_filesystem table creation script has it hardcoded to "BLOB" for all three applicable database types ("mysql", "postgres", "sqlite",) which causes the web2py_filesystem table creation to fail when starting py4web.