Alt Tab functionality

[JZB]

1. When in full screen mode, the Alt + Tab should be sent to the remote
computer. When in window mode Alt + Tab should be handled locally by the
client.

2. Since the Scroll Lock key is no longer present on most laptop
keyboards, it would be cool if there was another icon next to the chat
icon to switch Alt + Tab on/off on the remote computer.

I use Alt + Tab extensively in my work and find it difficult to open a
windows virtual keyboard just to click Scroll Lock every time I want to
use Alt + Tab on the remote.