Avoid deleting and setting identical voice commands

[theresalech]

Bug Report

Currently, setting voice commands doesn't check for a diff of which voice commands are in the old and new lists. This results in a case where if voice commands are set like so:

voiceCommands = [command1, command2, command3]
voiceCommands = [command1, command2, command3, command 4]

What will happen is command1/2/3 will be set to the head unit, then command1/2/3 will be deleted from the head unit, then command1/2/3/4 will be set to the head unit.

Because voice commands can be so slow to process, we should diff and only set / delete what is necessary instead of taking an all-or-nothing approach.