Add installation.xml and fix errors in knot.xml

doc/installation.xml

+<chapter>
+  <title>Knot DNS Installation</title>
+  <para>
+    Install userspace-rcu and run ./configure &amp;&amp; make &amp;&amp; make install
+  </para>
+</chapter>

doc/knot.xml

@@ -18,7 +18,7 @@
 	<firstname>Ondřej</firstname><surname>Surý</surname>
 	<email>ondrej.sury@nic.cz</email>
 	<affiliation>CZ.NIC, z.s.p.o.</affiliation>
-      </personame>
+      </personname>
     </author>
     <copyright><year>2012</year><holder>CZ.NIC, z.s.p.o.</holder></copyright>
   </info>