Fix yourproject rendering problem in HTML

At least on the [github.io](http://twitter.github.io/scala_school/sbt.html) version, it used to render as `project/build/.scala` which is of course nonsense. By using fixed-width fonting, it makes the literal text and the variable text easier to distinguish, without resorting to characters that are meaningful to HTML.

web/sbt.textile

@@ -69,23 +69,22 @@ Note that it's good form to start out with a SNAPSHOT version of your project.
 
 h2. Project Layout
 
-* project - project definition files
-** project/build/<yourproject>.scala - the main project definition file
-** project/build.properties - project, sbt and scala version definitions
-* src/main - your app code goes here, in a subdirectory indicating the
-code's language (e.g. src/main/scala, src/main/java)
-* src/main/resources - static files you want added to your jar
+* @project@ - project definition files
+** @project/build/@ _yourproject_ @.scala@ - the main project definition file
+** @project/build.properties@ - project, sbt and scala version definitions
+* @src/main@ - your app code goes here, in a subdirectory indicating the
+code's language (e.g. @src/main/scala@, @src/main/java@)
+* @src/main/resources@ - static files you want added to your jar
   (e.g. logging config)
-* src/test - like src/main, but for tests
-* lib_managed - the jar files your project depends on. Populated by sbt update
-* target - the destination for generated stuff (e.g. generated thrift
+* @src/test@ - like @src/main@, but for tests
+* @lib_managed@ - the jar files your project depends on. Populated by sbt update
+* @target@ - the destination for generated stuff (e.g. generated thrift
   code, class files, jars)
 
 h2. Adding Some Code
 
-We'll be creating a simple JSON parser for simple tweets.  Add the
-following code to
-src/main/scala/com/twitter/sample/SimpleParser.scala
+We'll be creating a simple JSON parser for simple tweets.  Add the following code to
+@src/main/scala/com/twitter/sample/SimpleParser.scala@
 
 <pre>
 package com.twitter.sample