Rover Driver PR4

• Fixed downslope detection on slope abort from triggering and possibly causing problems when the rover backs down
• FinishDrive now redraws the whole screen for when used after program is aborted by error or user
• Removed the deprecated brakeOverUse variable
• Fixed how approach speed multipliers were being applied - was subtracting from a negative number to decrease it towards 0 instead of adding
• The amount of time until the monitor program kicks in is now settable. Mainly to allow rover to get up to speed to avoid slope aborts when restarting on unlevel terrain
• Wasn't using the currentBrakeTime environment variable properly in cases of extremeSlopeAngle to modify the braking length
• Added highest/lowest altitude drive stats
• Reset some environment variables in ResumeDrive to avoid restarting in weird states
• Removed flickering from real-time output window at the very slight expense of update frequency
• Redid the Rover Variables section of the real-time output window to make it possible to see the behavior of the rover on various slope angles without needing a ton of log spam