18effa8a-ls166

LinuxServer Changes:

Install XMLTV from Alpine repos.

tvheadend Changes:

• fixed bug with _lang3_to_lang2()
  Typo made using lang instead of lang3 in lookup map
• clean by running through autopep8
• Add more exception handling to prevent it crashing
  Still needs some improvements with exception types
• tidy up for pylint
• python 2 is deprecated - simplify for python 3