big eigen2support fix, aimed at users who relied on internal eigen2 stuff: now we dont need customizations in test/eigen2/main.h anymore.

These tests already build:
eigen2_basicstuff
eigen2_adjoint
eigen2_linearstructure
eigen2_prec_inverse_4x4

Eigen/src/Core/NumTraits.h

@@ -69,6 +69,12 @@ template<typename T> struct GenericNumTraits
     AddCost = 1,
     MulCost = 1
   };
+  
+#ifdef EIGEN2_SUPPORT
+  enum {
+    HasFloatingPoint = !IsInteger
+  };
+#endif
 
   typedef T Real;
   typedef typename internal::conditional<