doc: fix sphinx and doxygen build errors

doc/tutorial/source/getting-started.rst

@@ -326,10 +326,8 @@ following::
    uan                       virtual-net-device        visualizer               
    wave                      wifi                      wimax                    
    
-Modules not built (see ns-3 tutorial for explanation):
-brite                     click   
-
-   Leaving directory `./ns-3.25'
+   Modules not built (see ns-3 tutorial for explanation):
+   brite                     click   
 
 Regarding the portion about modules not built::
 
@@ -360,7 +358,7 @@ and you should see something like::
   >> Building pybindgen-0.17.0.post49+ng0e4e3bc - OK
   >> Building ns-3.25 - OK
 
-*Hint:  you can also perform both steps, download and build, by calling 'bake.py deploy'.*
+*Hint:  you can also perform both steps, download and build, by calling ``bake.py deploy``.*
 
 If there happens to be a failure, please have a look at what the following
 command tells you; it may give a hint as to a missing dependency::
@@ -506,10 +504,10 @@ Okay, sorry, I made you build the |ns3| part of the system twice,
 but now you know how to change the configuration and build optimized code.
 
 A command exists for checking which profile is currently active
-for an already configured project:
+for an already configured project::
 
   $ ./waf --check-profile
-  Waf: Entering directory `/path/to/ns-3-allinone/ns-3.25/build'
+  Waf: Entering directory \`/path/to/ns-3-allinone/ns-3.25/build'
   Build profile: debug
 
 The build.py script discussed above supports also the ``--enable-examples``

src/network/doc/queue-limits.rst

@@ -1,5 +1,5 @@
 Queue limits
-------
+------------
 
 .. heading hierarchy:
    ------------- Chapter

src/network/model/packet-tag-list.h

@@ -75,7 +75,7 @@ class Tag;
  *          T2:n -> T1:l ;
  *          T1:n -> NULL ;
  *        };
- *      };
+ *      }
  * \enddot
  *
  *   - Tags are stored in serialized form in a tree of TagData

src/traffic-control/doc/pie.rst

@@ -38,7 +38,9 @@ References
 
 .. [Pan16] R. Pan, P. Natarajan, F. Baker, G. White, B. VerSteeg, M.S. Prabhu, C. Piglione, V. Subramanian, Internet-Draft: PIE: A lightweight control scheme to address the bufferbloat problem, April 2016.  Available online at `<https://tools.ietf.org/html/draft-ietf-aqm-pie-07>`_.
 
-.. [Buf14] Bufferbloat.net.  Available online at `<http://www.bufferbloat.net/>`_.
+.. comment
+   This ref defined in codel.rst:
+   [Buf14] Bufferbloat.net.  Available online at `<http://www.bufferbloat.net/>`_.
 
 Attributes
 ==========