static XmlElement AddImportElement(
			this MSBuildProject project,
			string importedProjectFile,
			ProjectImportLocation importLocation)
		{
			if (importLocation == ProjectImportLocation.Top) {
				return project.AddImportElementAtTop (importedProjectFile);
			}
			XmlElement import = project.CreateImportElement (importedProjectFile);
			project.Document.DocumentElement.AppendChild (import);
			return import;
		}
		static XmlElement AddImportElementAtTop (this MSBuildProject project, string importedProjectFile)
		{
			XmlElement import = project.CreateImportElement (importedProjectFile);
			XmlElement projectRoot = project.Document.DocumentElement;
			projectRoot.InsertBefore (import, projectRoot.FirstChild);
			return import;
		}