* added new platform for the Unitymedia Horizon HD Recorder
* improve connection handling of the horizon platform
* remove unneeded parameters and fix spelling in the horizon platform
* abort or raise exception if connection to the device could not be established
* remove channel/source list and SELECT_SOURCE feature
* remove useless type check after cast and use a try block instead
* abort or raise exception if reconnect to device fails
* remove protocol specific code and restructure sending logic accordingly
* fix indentation to be pep8 complaint
* remove unused methods/properties
* fix unnecessary pylint commands and use a return to abert outside of setup_platform
* directly access config values
Paulus Schoutsen
Ville Skyttä
Ben Lebherz