improved style of docs

doc/index.html

@@ -854,7 +854,7 @@ sudo gcc_select gcc40</pre>
 
     <li>
         <p>
-        Grep through the src/*.mk files
+        Grep through the <code>src/*.mk</code> files
         to find a project that is most similar to yours.
         (Really, <code>grep</code> is your friend here.)
         </p>
@@ -962,7 +962,7 @@ https://...</pre>
         </p>
 
         <p>
-        At the very end of your *.mk file
+        At the very end of your <code>*.mk</code> file
         you should build the test program in a generic way,
         using strict compiler flags.
         The last few lines of
@@ -983,9 +983,9 @@ https://...</pre>
 
     <li>
         <p>
-        Check that you don't have "dirty stuf" in your *.mk files,
+        Check that you don't have "dirty stuf" in your <code>*.mk</code> files,
         such as TAB characters or trailing spaces at lines endings.
-        Have a look at random *.mk files
+        Have a look at random <code>*.mk</code> files
         to get a feeling for the coding style.
         </p>