Fixed comment bug

[SVN r14216]

include/boost/preprocessor/tuple.hpp

@@ -24,9 +24,9 @@ constitutes a single macro parameter.</p>
 <p>Examples of tuples:</p>
 
 <pre>
-(const, volatile)    /* 2-tuple */
-(*, /, %)            /* 3-tuple */
-(1, "2", '3', (4,5)) /* 4-tuple */
+(const, volatile)       a 2-tuple
+(*, /, %)               a 3-tuple
+(1, "2", '3', (4,5))    a 4-tuple
 </pre>
 
 <p>Tuples can be used for representing structured data.</p>