Update V4.0 top level README (#585)

TYPE: text only

KEYWORDS: README

SOURCE: internal

DESCRIPTION OF CHANGES:
Update this README file for V4.0

LIST OF MODIFIED FILES:
M README

TESTS CONDUCTED:
No tests.

Author: weiwangncar

README

@@ -1,4 +1,4 @@
-WRF Model Version 4.0 Friendly #2 (April 30, 2018)
+WRF Model Version 4.0 (June 8, 2018)
 http://wrf-model.org/users/users.php
 
 ------------------------
@@ -40,6 +40,13 @@ doc/README.rsl_output
 doc/README.windturbine
 doc/README_test_cases
 
+V4.0 Release Notes (6/8/2018):
+-------------------
+
+- For more information on WRF V4.0 release, visit WRF User's home pages
+  http://www2.mmm.ucar.edu/wrf/users/, and
+  http://www.dtcenter.org/wrf-nmm/users/, and read the online User's Guide.
+
 V3.9.1.1 Release Notes (8/28/17):
 -------------------
 
@@ -285,6 +292,7 @@ WRF update history:
 - V3.9: Apr 17, 2017
 - V3.9.1: Aug 17, 2017
 - V3.9.1.1: Aug 28, 2017
+- V4.0: June 8, 2018
 
 ======================================
 
@@ -371,7 +379,7 @@ How to compile and run?
 
 ======================================
 
-What is in WRF V3?
+What is in WRF V4?
 
 - Advanced Research WRF (ARW) solver: Eulerian mass, hydrostatic and non-hydrostatic
   * Arakawa C-grid staggering
@@ -405,7 +413,7 @@ What is in WRF V3?
   * microphysics (Kessler/ WRF Single Moment 3, 5 and 6 classes / Lin et al./ Mibrandt 2-moment /
     Eta Ferrier / Thompson / Goddard / 2-moment Morrison / WRF Double Moment 5 and 6 classes /
     SBU-Lin 5-classes / NSSL 2-moment and 1-moment / CAM 5.1 ) / Thompson aerosol-aware /
-    HUJI full and fast SBM / P3
+    HUJI full and fast SBM / P3 / 2-moment Morrison with CESM aerosol
   * cumulus parameterization (Kain-Fritsch with shallow convection / 
     Betts-Miller-Janjic / Grell-Devenyi ensemble / Grell 3D (with shallow convection option) /
     Grell-Freitas ensemble /