Update README

README.md

-Nektar++
+Nektar++/tutorial
 ========
-Nektar++ is an open-source software framework designed to support the
+Nektar++/tutorial contains some useful tutorials associated to the open-source 
+software framework Nektar++. The software is designed to support the
 development of high-performance scalable solvers for partial differential
 equations (PDEs) using the spectral/hp element method.
 
-This repository contains the tutorials associated to the library.
-These are still under development and will be published as soon as ready.
+The tutorials are still under development and will become available shortly.
 
-A software and User Guide is available for download from
-<http://www.nektar.info/>.
+Note that the User Guide is available for download from <http://www.nektar.info/>.