docs: minimum required python mako version is 0.3.4

Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com>

docs/install.html

@@ -39,7 +39,7 @@ Version 2.6.4 or later should work.
 </li>
 <br>
 <li><a href="http://www.makotemplates.org/">Python Mako module</a> -
-Python Mako module is required. Version 0.7.3 or later should work.
+Python Mako module is required. Version 0.3.4 or later should work.
 </li>
 </br>
 <li><a href="http://www.scons.org/">SCons</a> is required for building on