Update speed-sensitive-volume.sh

[neon-dev]

• optimized sleep times - more responsive volume adjustment shouldn't increase overall car api calls by much, due to additional if clauses
• added config value for speed steps (now 8 mph instead of 10 mph) and reduced volume increment to smoothen things out
• added config value for minimum speed at which volume control will start
• added speed diff condition to avoid corner cases where volume could constantly jump between two values
• simplified value conversions and getting/setting of data values
• fixed volume 0 didn't stay at 0
• removed min volume config (min is one increment above volume level 0 now)
• removed max volume config (sense of this script is to keep volume subjectively at the same level)
• reread volume after adjusting it to accomodate for capping and rounding by mcu

[neon-dev]

I just realized apps run in a chroot jail (i don't use freedomev), so the lv/sdv commands are maybe not accessible from this environment.