share: change default iframe size, and remove border
share: change default iframe size, and remove border

From 600*400 to 100%*600

ether/etherpad-lite,storytouch/etherpad-lite,joequant/etherpad-lite,storytouch/etherpad-lite,ether/etherpad-lite,joequant/etherpad-lite,ether/etherpad-lite,storytouch/etherpad-lite,joequant/etherpad-lite,joequant/etherpad-lite