Merge branch 'release/0.20.0'

* release/0.20.0: (107 commits)
  Update Changelog
  Avoid gazillion warnings
  atlas::libary::initialize -> atlas::initialize
  Compatibility fixes
  Fix install script
  Disable export tests by default ( feature EXPORT_TESTS )
  ATLAS-266 Remove AccessMode from ArrayView API
  ATLAS-267 Tidy the atlas apps
  Fix warnings
  Fix warnings
  Fix warnings
  Fix compilation for packages using Atlas when gridtools backend is used
  Fix propagation of gridtools target
  Cosmetic changes in toplevel CMakeLists.txt
  ATLAS-265 Port to ecbuild3
  ATLAS-264 Workaround PGI compiler bug in test
  Fix StructuredMeshGenerator for y_numbering > 0
  Move unused and esotheric apps to sandbox
  Introduce convenience functions for initialisation and finalisation
  Make atlas::mpi::comm() cache a eckit::mpi::Comm reference for speed
  ...

CHANGELOG.md

@@ -7,6 +7,25 @@ This project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html
 
 ## [Unreleased]
 
+## [0.20.0] - 2019-03-06
+### Fixed
+- Pole edges hould not be created for global regular grids with points at poles
+- Update compatibility with more recent GridTools 
+- HaloExchange with CUDA
+- Self registration from external library
+
+### Added
+- Proj-based projections
+- OpenMP functions for sorting, filling, copying
+- Parallel structured grid interpolation
+
+### Changed
+- Grid iterators can have random access
+- Speed improvements for StructuredColumns constructor
+- Speed improvements for LonLatPolygon::contains()
+- Port to ecbuild 3 (also minimum required version)
+- Tidying up of atlas tools 
+
 ## [0.19.2] - 2020-01-28
 ### Changed
 - Compatibility with eckit 1.7 due to API change in eckit::LocalConfiguration
@@ -157,6 +176,7 @@ This project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html
 ## 0.13.0 - 2018-02-16
 
 [Unreleased]: https://github.com/ecmwf/atlas/compare/master...develop
+[0.20.0]: https://github.com/ecmwf/atlas/compare/0.20.0...0.19.2
 [0.19.2]: https://github.com/ecmwf/atlas/compare/0.19.1...0.19.2
 [0.19.1]: https://github.com/ecmwf/atlas/compare/0.19.0...0.19.1
 [0.19.0]: https://github.com/ecmwf/atlas/compare/0.18.1...0.19.0