Improve documentation

remove ambiguous part about smack-core being the only required
library. It's the only required library of *Smack*, but some user could
understand that Smack itself has no other dependencies. In order to
avoid such confusion, simply remove that part.

documentation/gettingstarted.html

@@ -29,8 +29,8 @@ to be as small as possible. The library ships as several JAR files to provide mo
 over which features applications require:
 
 <ul>
-    <li><tt>smack-core.jar</tt> -- provides core XMPP functionality and is the only <b>required</b>
-    library. All XMPP features that are part of the XMPP RFCs are included.</li>
+    <li><tt>smack-core.jar</tt> -- provides core XMPP functionality. All XMPP features that are
+    part of the XMPP RFCs are included.</li>
     <li><tt>smack-extensions.jar</tt> -- support for many of the extensions (XEPs) defined
     by the XMPP Standards Foundation, including multi-user chat, file transfer, user search, etc.
     The extensions are documented in the <a href="extensions/index.html">extensions manual</a>.</li>
@@ -52,7 +52,6 @@ over which features applications require:
     is enabled.</li>
 </ul>
 
-
 <p class="subheader">Configuration</p>
 Smack has an initialization process that involves 2 phases.
 <ul>

resources/releasedocs/README.html

@@ -167,8 +167,7 @@ fixes to the code, please visit the
  
 <p><b>About the Distribution</b><p>
 
-The <tt>smack.jar</tt> file in the main distribution folder is the only binary file 
-required for embedding XMPP functionality into client applications. The optional 
+The <tt>smack-core.jar</tt> file in the main distribution folder. The optional
 <tt>smack-extensions.jar</tt> contains the <a href="documentation/extensions/index.html">Smack extensions</a> 
 while <tt>smack-debug.jar</tt> contains an enhanced debugger.<p>