Bugfix for project_hexes. There is a hardwired earth_radius in addition to

the earth_radius_km that users can set in the namelist.  If the two are not the
same then the x,y,z locations will not be exactly on the unit sphere, and this
can cause problems in other utilities.  The bugfix has the algortithm use the
user-input earth_radius_km everywhere.

Author: skamaroc

mesh_tools/hex_projection/project_hexes.f90

@@ -57,7 +57,7 @@ program project_hexes
   integer, allocatable, dimension(:) :: indexToCellID, indexToVertexID, indexToEdgeID
 
   real(dp), allocatable, dimension(:) :: dcEdge, dvEdge
-  real(dp), parameter :: earth_radius = 6378.14_dp*1000.0_dp  ! meters
+  real(dp) :: earth_radius
   real(dp) :: invRadius, invRadius2
 
   real(dp) :: nominalMinDc
@@ -878,6 +878,7 @@ program project_hexes
 
   ! set mesh on a unit sphere - this is what init_atmosphere expects - it will expand it to the full sphere.
 
+  earth_radius = 1000.0_dp*earth_radius_km
   invRadius = 1.0_dp/earth_radius
   invRadius2 = invRadius*invRadius