fixed some imports in the __init__ files
fixed some imports in the test files
making VPD an Enum
Merge branch 'master' of https://github.com/rosjat/python-scsi
merged check_bit branch into master
Merge pull request #12 from rosjat/decode_all_bit_and_errors

merge decode_all_bit and  metaclasses to master 

there are also some minor changes in the converter module