OF-546 / OF-1326: Made compatible with API changes.

The Openfire plugin developer guide states that 'additinal' files should be in /classes/. Apparently, the old Ant script also included any files in the /src/. The new Maven structure does not.
To work around compatibility issues, code that was in /src/ is now moved to /classes/. This should work with both Ant, as well as Maven.

Additionally, this plugin now makes use of the new HttpBindManager API for registering contexts with the BOSH context. I do wonder if this plugin has any reason to be here though. Can't it just run its own embedded Jetty server?

src/plugins/jmxweb/changelog.html

@@ -42,6 +42,13 @@
 <h1>
 </h1>
 
+<p><b>0.0.6</b> -- May 8 2017</p>
+
+<ul>
+    <li>[<a href='https://igniterealtime.org/issues/browse/OF-1326'></a>] - Made compatible with new HttpBind API in Openfire 4.2.0</li>
+    <li>Minimum server requirement: 4.2.0 Alpha</li>
+</ul>
+
 <p><b>0.0.5</b> -- June 20 2016</p>
 
 <ul>