python: Fix issues introduced in latest 4k API changes
    
    Fix few issues in the latests 4k API changes:
    - Fix ValueError when using align=8388608 - a break was missing.
    - Remove the unneeded ALIGNX and SECTORX constants - seems that David
      merged an older version of the patch which did not remove them.
    - Fix capitalization and punctuation in new comments.
    - Remove trailing whitespace.
    - Wrap long enum difinition.
    
    Signed-off-by: Nir Soffer <nsoffer@redhat.com>