Port Ceres to Windows

This is a preliminary, but full, port of Ceres to Windows.
Currently all tests compile and run, with only system_test
failing to work correctly due to a path issue.

Change-Id: I4152c1588bf51ffd7f4d9401ef9759f5d28c299c
diff --git a/internal/ceres/trust_region_minimizer_test.cc b/internal/ceres/trust_region_minimizer_test.cc
index d87c963..03297c0 100644
--- a/internal/ceres/trust_region_minimizer_test.cc
+++ b/internal/ceres/trust_region_minimizer_test.cc
@@ -131,7 +131,7 @@
             1.0,
             0.0,
             0.0,
-            sqrt(10) * 2.0 * (x1 - x4) * (1.0 - x4);
+            sqrt(10.0) * 2.0 * (x1 - x4) * (1.0 - x4);
       }
       if (col2) {
         jacobian_matrix.col(column_index++) <<
@@ -154,7 +154,7 @@
             0.0,
             -sqrt(5.0),
             0.0,
-            sqrt(10) * 2.0 * (x1 - x4) * (x1 - 1.0);
+            sqrt(10.0) * 2.0 * (x1 - x4) * (x1 - 1.0);
       }
       VLOG(1) << "\n" << jacobian_matrix;
     }