Remove unnecessary charactors in string to prevent bad UI layout.

	modified:   lib/mdisc/menu.rb
	modified:   lib/mdisc/screen.rb
	modified:   lib/mdisc/ui.rb
Add player an input option: --continue, which aims at
play a song continuously in case the network becomes offline
occasionally.

	modified:   lib/mdisc/player.rb
	modified:   lib/mdisc/version.rb