fix markdown in readme

README.md

@@ -10,8 +10,8 @@ Usage
 
 with:
 
-    pro               [GetDP](http://getdp.info) .pro file
-    mesh              [Gmsh](http://gmsh.info) .msh file
+    pro               GetDP .pro file
+    mesh              Gmsh .msh file
     resolution        resolution from .pro file
     origin            circular contour origin (complex)
     radius            circular contour radius