Merge branch 'terencehill/scoreboard_panel_2' into 'master'

Merge branch 'terencehill/scoreboard_panel_2' into 'master'

Scoreboard panel

Make the scoreboard a panel (no HUD editor support): Scoreboard, Accuracy stats, Rankings and Map stats now can be shown with panel borders.

While working on it I fixed these minor bugs:
* text not vertically centered in the table rows
* incorrect scoreboard/HUD fading on quick (repeated) press/release of the scoreboard key
* inverted behaviour of the scoreboard key when the game is paused (or during a timeout)
* bad truncation position of player name when there's an icon ahead of it
* Get rid of a warning in the console when starting a game: "fixed missing field ''"

See merge request !345