title: undefined symbol: luaopen_LuaXml
body: <p>I had installed luaxml module using luarocks. I had used the luaxml to call in a lua script. But getting an error </p>
  
  <p>Lua script:</p>
  
  <pre><code>xml = require("LuaXml");
  local xobj = xml.eval('&lt;Cmd Message="Hello"/&gt;');
  session:consoleLog("INFO","The message in the XML is "..xobj["Message"].."\n");
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>mod_lua.cpp:203 error loading module 'LuaXml' from file '/usr/local/lib/lua   
  /5.2/LuaXML_lib.so': /usr/local/lib/lua/5.2/LuaXML_lib.so: undefined symbol:  
  luaopen_LuaXml
  stack traceback:
  [C]: ?
  [C]: in function 'require'
  </code></pre>
  
  <p>I had seen the concept of add libraries to Lua dynamically but i couldn't understand. Can anyone help me out. Briefly so that how to link the core module luaxml with the script. 
  Another question how can i test whether the installed module luaxml through luarocks is installed or not.  </p>