Markup user input in screens

[SVN r26281]

doc/tutorial.xml

@@ -77,14 +77,13 @@ if (vm.count("compression")) {
   <para>It's now a good time to try compiling the code yourself, but if
     you're not yet ready, here's an example session:
 <screen>
-$bin/gcc/debug/first
+$<userinput>bin/gcc/debug/first</userinput>
 Compression level was not set.
-$bin/gcc/debug/first --help
+$<userinput>bin/gcc/debug/first --help</userinput>
 Allowed options:
   --help                 : produce help message
   --compression arg      : set compression level
-
-$bin/gcc/debug/first --compression 10
+$<userinput>bin/gcc/debug/first --compression 10</userinput>
 Compression level was set to 10.
     </screen>
   </para>
@@ -135,11 +134,11 @@ desc.add_options()
   <para>The "input-file" option specifies the list of files to
     process. That's okay for a start, but, of course, writing something like:
     <screen>
-compiler --input-file=a.cpp
+<userinput>compiler --input-file=a.cpp</userinput>
     </screen>
     is a little non-standard, compared with
     <screen>
-compiler a.cpp
+<userinput>compiler a.cpp</userinput>
     </screen>
     We'll address this in a moment.
   </para>
@@ -192,7 +191,7 @@ cout &lt;&lt; &quot;Optimization level is &quot; &lt;&lt; opt &lt;&lt; &quot;\n&
 
   <para>Here's an example session:
     <screen>
-$bin/gcc/debug/options_description --help
+$<userinput>bin/gcc/debug/options_description --help</userinput>
 Usage: options_description [options]
 Allowed options:
   --help                 : produce help message
@@ -201,7 +200,7 @@ Allowed options:
   --input-file arg       : input file
 $bin/gcc/debug/options_description
 Optimization level is 10
-$bin/gcc/debug/options_description --optimization 4 -I foo a.cpp
+$<userinput>bin/gcc/debug/options_description --optimization 4 -I foo a.cpp</userinput>
 Include paths are: foo
 Input files are: a.cpp
 Optimization level is 4
@@ -301,10 +300,10 @@ visible.add(generic).add(config);
 
     <para>Here's an example session:
 <screen>
-$bin/gcc/debug/multiple_sources
+$<userinput>bin/gcc/debug/multiple_sources</userinput>
 Include paths are: /opt
 Optimization level is 1
-$bin/gcc/debug/multiple_sources --help
+$<userinput>bin/gcc/debug/multiple_sources --help</userinput>
 Allows options:
 
 Generic options:
@@ -315,7 +314,7 @@ Configuration:
   --optimization n       : optimization level
   -I [ --include-path ] path : include path
 
-$bin/gcc/debug/multiple_sources --optimization=4 -I foo a.cpp b.cpp
+$<userinput>bin/gcc/debug/multiple_sources --optimization=4 -I foo a.cpp b.cpp</userinput>
 Include paths are: foo /opt
 Input files are: a.cpp b.cpp
 Optimization level is 4