x-terminal-emulator is wrapper for system default

http://unix.stackexchange.com/questions/32547/how-to-launch-an-application-with-default-terminal-emulator-on-ubuntu

The other way around is https://github.com/wbond/sublime_terminal/blob/master/Terminal.py#L85
Merge pull request #6 from dz0ny/patch-1

x-terminal-emulator is wrapper for system default