Removed MSVC warnings
These are warnings which show up when using Ceres.

Change-Id: Id1f382f46b8a60743f0b12535b5b3cdf46f988e0

include/ceres/fpclassify.h

diff --git a/include/ceres/fpclassify.h b/include/ceres/fpclassify.h
index e7f0d7c..da8a4d0 100644
--- a/include/ceres/fpclassify.h
+++ b/include/ceres/fpclassify.h
@@ -47,9 +47,9 @@
 
 #if defined(_MSC_VER)
 
-inline bool IsFinite  (double x) { return _finite(x);                }
-inline bool IsInfinite(double x) { return !_finite(x) && !_isnan(x); }
-inline bool IsNaN     (double x) { return _isnan(x);                 }
+inline bool IsFinite  (double x) { return _finite(x) != 0;                   }
+inline bool IsInfinite(double x) { return _finite(x) == 0 && _isnan(x) == 0; }
+inline bool IsNaN     (double x) { return _isnan(x) != 0;                    }
 inline bool IsNormal  (double x) {
   int classification = _fpclass(x);
   return classification == _FPCLASS_NN ||

include/ceres/local_parameterization.h

diff --git a/include/ceres/local_parameterization.h b/include/ceres/local_parameterization.h
index 3ecd959..0d74087 100644
--- a/include/ceres/local_parameterization.h
+++ b/include/ceres/local_parameterization.h
@@ -160,7 +160,7 @@
                     double* x_plus_delta) const;
   virtual bool ComputeJacobian(const double* x,
                                double* jacobian) const;
-  virtual int GlobalSize() const { return constancy_mask_.size(); }
+  virtual int GlobalSize() const { return static_cast<int>(constancy_mask_.size()); }
   virtual int LocalSize() const { return local_size_; }
 
  private: