Doxygen fixes. Bizarre: doxygen seems to parse some headers OK and others not.

gtsam/base/BTree.h

@@ -9,7 +9,7 @@
 
  * -------------------------------------------------------------------------- */
 
-/*
+/**
  *  Created on: Feb 3, 2010
  *  @brief: purely functional binary tree
  *  @Author: Chris Beall

gtsam/base/DSF.h

@@ -9,12 +9,12 @@
 
  * -------------------------------------------------------------------------- */
 
-/*
+/**
  * DSF.h
  *
  *  Created on: Mar 26, 2010
- *  Author: nikai
- *  Description: An implementation of Disjoint set forests (see CLR page 446 and up)
+ *  @Author Kai Ni
+ *  @brief An implementation of Disjoint set forests (see CLR page 446 and up)
  *  						 Quoting from CLR: A disjoint-set data structure maintains a collection
  * 							 S = {S_1,S_2,...} of disjoint dynamic sets. Each set is identified by
  * 							 a representative, which is some member of the set.

gtsam/base/DSFVector.h

@@ -12,10 +12,10 @@
 /*
  * DSFVector.h
  *
- *   Created on: Jun 25, 2010
- *       Author: nikai
- *  Description: a faster implementation for DSF, which uses vector rather than btree.
- *               As a result, the size of the forest is prefixed.
+ * Created on: Jun 25, 2010
+ * @Author nikai
+ * @brief a faster implementation for DSF, which uses vector rather than btree.
+ * As a result, the size of the forest is prefixed.
  */
 
 #pragma once