Add missing "import sys" statement to fix "solfege -h". Reported by Tommi Siivola. elembuilder: do not popup a new windows and display the music in it if have_music_displayer=no. Fixed by Tommi Siivola. Updated Italian translations. Added Polish screenshots and updated the Norwegians. Simplified Chinese translations for GNU Solfege by Fan Rui and Ji ZhengYu.