Copy line up/down key binding not working in Linux

[vsccarl]

• VSCode Version: 1.0.0 (present in release and latest alpha)
• OS Version: Ubuntu 15.10

Steps to Reproduce:

1. Navigate to a line
2. Press Ctrl+Alt+Shift+UpArrow (or DownArrow)

Actual:
Nothing happens.

[Tyriar]

Duplicate of #1782, I'll have another look at whether there are any available keybindings that don't conflict with Ubuntu's workspace defaults.

[Tyriar]

Closing in favor of #509