Clarified some comments

--HG--
extra : convert_revision : svn%3Afdd8eb12-d10e-0410-9acb-85c331704f74/trunk%403995

dlib/matrix/symmetric_matrix_cache.h

@@ -177,7 +177,7 @@ namespace dlib
             init();
             make_sure_next_is_unreferenced();
 
-            // if the lookup table is pointing to cache(next,*) then clear lookup[next]
+            // if the lookup table is pointing to cache[next] then clear lookup[next]
             if (rlookup[next] != -1)
                 lookup[rlookup[next]] = -1;
 

dlib/optimization/optimization_solve_qp2_using_smo_abstract.h

@@ -71,8 +71,8 @@ namespace dlib
                   Where f is convex.  This means that Q should be symmetric and positive-semidefinite.
                 
                 
-                This object implements the strategy used by the LIBSVM tool and described 
-                by the following papers:
+                This object implements the strategy used by the LIBSVM tool.  The following papers
+                can be consulted for additional details:
                     - Chang and Lin, Training {nu}-Support Vector Classifiers: Theory and Algorithms
                     - Chih-Chung Chang and Chih-Jen Lin, LIBSVM : a library for support vector 
                       machines, 2001. Software available at http://www.csie.ntu.edu.tw/~cjlin/libsvm