rstudio-wrapper-portlet/src/main/webapp/WEB-INF/liferay-display.xml

<?xml version="1.0"?>
<!DOCTYPE display PUBLIC "-//Liferay//DTD Display 6.0.0//EN" "http://www.liferay.com/dtd/liferay-display_6_0_0.dtd">

<display>
	<category name="gCube Applications">
		<portlet id="RStudioWrapper" />
	</category>
</display>