Convert exponential F to Display F

[Tim Hewitt]

I've written some really _ugly_ code to convert a string from exponential format
as returned by the Float Manager FlpFToA call to a display format suitable for humans.

I must admit my string processing skills in C are not good.  Would anyone care
to take a stab at a clean way to convert from

   [-]x.yyyyyyyye[-]zz
   
to

   [-]x.y
   
Thanks,

-Tim