Remove future looking comments from types.h

Change-Id: I2c801980778e2575ef8eaa52eafbdb3724f1ae01
diff --git a/include/ceres/types.h b/include/ceres/types.h
index 643eb23..a4a4861 100644
--- a/include/ceres/types.h
+++ b/include/ceres/types.h
@@ -421,17 +421,6 @@
 enum CovarianceAlgorithmType {
   DENSE_SVD,
   SPARSE_QR,
-
-  // TODO(sameeragarwal): Expand this to include
-  // DENSE_QR (Eigen)
-  // DENSE_SCHUR_SVD (Eigen)
-  // SPARSE_SCHUR_LU (Eigen, SuiteSparse)
-  //
-  // Are the following two a good idea? given that they are not rank
-  // revealing.
-  //
-  // DENSE_SCHUR_CHOLESKY (Eigen)
-  // SPARSE_SCHUR_CHOLESKY (Eigen, SuiteSparse)
 };
 
 // It is a near impossibility that user code generates this exact