br: make altgr+e produce degree, not euro sign

It appears that users expect this key to be degree. I did a little bit of searching, and while I did find a few references to this being euro sign (e.g., on Wikipedia page 1), it looks like most photos of Brazillian keyboards I could find have this as degree, and the user expectation is that this is degree 2.

For what it's worth, it appears Microsoft Windows has this as degree (tested on Windows 7).

Signed-off-by: Jack Rosenthal jrosenth@chromium.org