Write the XWiki XML RPC model in .NET.

At the moment XWord uses services provided by wiki pages(velocity + groovy scripting). This is somewhat unsafe and it's difficult to synchronize the server package(a XAR) distribution with the ClickOnce deployment system.
Necessary steps:

• Write the XML RPC model;
• Create an XML RPC proxy that uses the model;
• Create an adapter for the proxy and implement IXWikiClient interface. Replace the current implementation(XWikiHttpCLient) with the new one.
  ...
• Enrich the api with new methods like syntax conversion, get available syntaxes, etc.