Fixes html entities to prevent parsing error of generated documentation.

The html output contained "<style> and </style>" which causes a parse
error on stricter html validators. The solution was to swap < and > for
the equivalent html entities &lt; and &gt; respectivelly.

Signed-off-by: André Tannús <atannus@epungo.com.br>
Merge pull request #334 from atannus/develop

Fixes html entities to prevent parsing error of generated documentation.