IMCI fixes. Thought I had committed these. The "real" disambiguation

between std::real and Grid::real shouldn't have been necessary and I don't
know why only the icpc v16.0 on babbage hits it.
May need a longer term rename of Grid::real or some careful EnableIf work.

tests/Test_synthetic_lanczos.cc

@@ -67,7 +67,7 @@ public:
 
     random(pRNG,scale);
 
-    scale = exp(-real(scale)*3.0);
+    scale = exp(-Grid::real(scale)*3.0);
     std::cout << " True matrix \n"<< scale <<std::endl;
   }