Merged in benoitsteiner/eigen-fixes/nvcc_fixes (pull request PR-53)

Silenced a compilation warning produced by nvcc.

Eigen/src/Core/util/Memory.h

@@ -89,7 +89,7 @@ inline void throw_std_bad_alloc()
   #ifdef EIGEN_EXCEPTIONS
     throw std::bad_alloc();
   #else
-    std::size_t huge = -1;
+    std::size_t huge = static_cast<std::size_t>(-1);
     new int[huge];
   #endif
 }