add some NEWS

NEWS.txt

@@ -1,20 +1,29 @@
            libSBML NEWS -- History of user-visible changes
 
 ====================================================================
-5.19.1 (Current development branch)
+5.20.0
 ====================================================================
-STABLE RELEASE
+
+Given the length of time since our last release the list of changes
+and acknowledgements of contributions is incomplete. We apologise and
+offer thanks to anyone who has been involved and those people who have
+contributed their spare time to continuing maintenance and development.
+
+* Addition of support for the SBML Spatial package
+
+  - Now that the first official version of the specification for the
+    SBML Level 3 Spatial package is available, the libSBML API for
+    'spatial' is now included in the stable release of libSBML. 
+    Thus a CMake build using '-WITH_STABLE_PACKAGES' will now include
+    the spatial package code.
 
 * New features
-
-  - 'comp' package-specific updates:
-  - 'distrib' package-specific updates:
-  - 'fbc' package-specific updates:
-  - 'groups' package-specific updates:
-  - 'layout' package-specific updates:
-  - 'multi' package-specific updates:
-  - 'qual' package-specific updates:
-  - 'render' package-specific updates:
+
+  - There is a new converter SBMLRateRuleConverter which will take 
+    a model with RateRules and infer the corresponding reaction network.
+    This is still considered under development and we would really
+    appreciate any feedback.
+
 
 * Bug fixes
 
@@ -28,39 +37,16 @@ STABLE RELEASE
     updated for Python 3.10 changes. Thanks to
     Zbigniew Jędrzejewski-Szmek for submitting the changes.
 
-  - 'comp' package-specific bug fixes:
-  - 'distrib' package-specific bug fixes:
-  - 'fbc' package-specific bug fixes:
-  - 'groups' package-specific bug fixes:
-  - 'layout' package-specific bug fixes:
-  - 'multi' package-specific bug fixes:
-  - 'qual' package-specific bug fixes:
-  - 'render' package-specific bug fixes:
-
 * Configuration/build system changes
 
   - Extensive continuous integration testing has been added to 
     the GitHub repository.
 
-
 * Miscellaneous
 
+  - Note there is now a Julia interface to libSBML available
+    at https://lcsb-biocore.github.io/SBML.jl/stable/
 
-EXPERIMENTAL PACKAGES
-
-* New features
-
-  - 'arrays' package-specific updates:
-  - 'dyn' package-specific updates:
-  - 'req' package-specific updates:
-  - 'spatial' package-specific updates:
-
- * Bug fixes
-
-  - 'arrays' package-specific bug fixes:
-  - 'dyn' package-specific bug fixes:
-  - 'req' package-specific bug fixes:
-  - 'spatial' package-specific bug fixes:
 
 ====================================================================
 5.19.0 (2020-11-27)