Bump Ceres version to 2.0.0

Due to the large amount of changes made as part of
the C++11 migration, it makes sense to have a
large version bump.

Change-Id: I2d81828e2d8e23f0829070726e7b3ec31d7f1724
diff --git a/include/ceres/version.h b/include/ceres/version.h
index 3ccd4c8..20fbe22 100644
--- a/include/ceres/version.h
+++ b/include/ceres/version.h
@@ -31,8 +31,8 @@
 #ifndef CERES_PUBLIC_VERSION_H_
 #define CERES_PUBLIC_VERSION_H_
 
-#define CERES_VERSION_MAJOR 1
-#define CERES_VERSION_MINOR 14
+#define CERES_VERSION_MAJOR 2
+#define CERES_VERSION_MINOR 0
 #define CERES_VERSION_REVISION 0
 
 // Classic CPP stringifcation; the extra level of indirection allows the