mint-arena: Add third person crosshair
mint-arena: Allow changing third person height offset

It helps aim because character isn't blocking crosshair as much.
Made it range checked instead of a cheat. Third person is a handicap anyway.
mint-arena: Increase cg_thirdPersonHeight to 24

It makes aimming easier.
mint-arena: Add cg_drawScores to disable drawing scores box on HUD
mint-arena: Add step view smoothing to third person

Smooth view position and (your own) player position.
mint-arena: Fix Q3 scoreboard highlighted line length

In Q3 it goes off the screen. In Spearmint widescreen it's abnormally long.

Back ported from Turtle Arena.