implement entire project in nodes

Project items are now represented directly in nodes opening up more versatility and possibilities. This is the first iteration of this and will be buggy. Need to test thoroughly.

app/task/project/save/save.cpp

@@ -46,13 +46,11 @@ bool ProjectSaveTask::Run()
     QXmlStreamWriter writer(&project_file);
     writer.setAutoFormatting(true);
 
-    writer.writeStartDocument();
-
-    writer.writeStartElement("olive");
-
     // Version is stored in YYMMDD from whenever the project format was last changed
     // Allows easy integer math for checking project versions.
-    writer.writeTextElement("version", QString::number(Core::kProjectVersion));
+    writer.writeStartDocument(QString::number(Core::kProjectVersion));
+
+    writer.writeStartElement("olive");
 
     writer.writeTextElement("url", project_->filename());