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