Modify fltxy2displacement.f
Modify fltxy2displacement.f

1. Add online usage subroutine that can be accessed
   via the command line.
2. If necessary files are not found, access help screen
   by typing "help".
3. Position of faults and stations are changed from meters
   to kilometers.

mherman09/Hdef,mherman09/Hdef,mherman09/Hdef