Log Message:
Update to 4.6.1.

4.6.1 Release Notes
-------------------

 o Upgraded to EPSG 6.17 version for nad/epsg.  Also corrected the precision
   problem introduced in the last version.

 o Added logic for tmerc projection to fail rather than return crazy results
   if more than 90 degrees away from the central meridian (#5).  This change
   may only be temporary till a more comprehensive solution is found.

 o Fixed handling of extra text in cs2cs.

 o Renamed INSTALL to INSTALL.TXT.

 o The eqc projection has been generalized to include a latitude of origin.

 o Added the glabsgm (Gauss Laborde / Sphere Geometric Mean) projection,
   and gstmerc variation.

 o nad/IGNF init catalogue created.

 o added the ntf_r93.gsb datum shift file.

 o Add /Op in nmake.opt compile options to avoid VC7 optimization bug (#12)

 o Fix testvarious test script so it works properly when grid files available