Updated Cairo version

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@36349 15284696-431f-4ddb-bdfa-cd5b030d7da7

REQUIREMENTS.html

@@ -157,7 +157,7 @@ gui/wxpython/README)<br>
     including libavcodec, libavformat, libswscale <BR>
 <a href="http://ffmpeg.mplayerhq.hu/">http://ffmpeg.mplayerhq.hu</a><BR>
 
-<li><B>Cairo</B> (Cairo graphics library, Version &gt;= XX)<BR>
+<li><B>Cairo</B> (Cairo graphics library, Version &gt;= 1.5.8)<BR>
 <a href="http://cairographics.org">http://cairographics.org</a><BR>
 
 <li><B>AVCE00 and E00Compr Libraries</B> (avcimport)<BR>