corrected the auto altitude line functionality
corrected colormap esrJet
font size and text stuff
enhanced elevation-only scans

- cardinal directions shown left/right on elevation scan x-axis
- altitude line drawn on map at 400 km to indicate show scan on map
- hidden altitude lines on flat plot
- drawn invisible coastlines on flat plot (otherwise the map axis isn't
  properly initiated)
- main plot title updated with new scan direction ('N-S' etc.)
- figure names updated with new scan direction ('N-S' etc.)
added km unit to altitude line labels
changed colormaps to nipy_spectral and coolwarm
unneeded code (I think)
fix to make onlyDoScanNo take precedence over startAt
auto-detection of existing scans will now overwrite latest scan
added input to control realtime and changed order of input prompts