Bug fixes and minor enhancements

Fixes #676 Server doesn't listen on IPv4 on Raspberry Pi enhancement question

Fixes #673 ha-bridge not working after restart bug

Fixes #618 Long Press for Harmony enhancement question

Fixes #608 Link-Button-Feature and Hue App bug question

Fixes #669 Need to re-pair Philips Hue Bridge enhancement question

Fixes #671 action taking place only on the second time i ask to do it enhancement question

Fixes #594 Buttons on Hue Devices page do not work bug question

Fixes #654 Add possibility to set qos and retained state of MQTT messages

Fixes #665 Hue Constant updates