RF: Refactor Jail and JailThread

Includes:
    - documentation to new format and use of properties
    - change isActive->is_active as former no longer documented for
      python3, and later introduction and documented in python2.6
    - status formatter in beautifier somewhat more automatically
      formatted; no changes are required for additional status elements
    - JailThread now set to active within `start` method, complimenting
      `stop` method
ENH+DOC: Update Fail2Ban database doc strings and use properties
Merge pull request #628 from kwirk/jail-refactor

RF: Refactor Jail and JailThread