Refactoring louloulibs and cmake

Use OBJECT libraries
Remove the louloulibs directory
Write FOUND variables in the cache

src/xmpp/body.hpp

@@ -0,0 +1,12 @@
+#pragma once
+
+
+namespace Xmpp
+{
+// Contains:
+// - an XMPP-valid UTF-8 body
+// - an XML node representing the XHTML-IM body, or null
+  using body = std::tuple<const std::string, std::unique_ptr<XmlNode>>;
+}
+
+