Update CHANGELOG for 0.3.0

Author: psalz

CHANGELOG.md

@@ -6,6 +6,68 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic
 Versioning](http://semver.org/spec/v2.0.0.html).
 
+## [0.3.0] - 2021-11-16
+
+We recommend using the following SYCL versions with this release:
+
+- ComputeCpp: 2.6.0 or newer
+- DPC++: 7735139 or newer
+- hipSYCL: 7b00e2e or newer
+
+### Added
+
+- Introduce aliases or custom implementations in `::celerity` namespace for most
+  supported SYCL features (e.g. `celerity::access_mode`, `celerity::item` and so
+  on). (c36f55e, 44c181e, f7ca077, 2588d7e, fd58422, e706db3, 7552445)
+- `CELERITY_PROFILE_KERNEL` is now also supported for hipSYCL. (0521e9e)
+- Add support for unnamed kernels (hipSYCL and DPC++ only). (7a3431e)
+- Add support for nd-range `parallel_for` alongside `local_accessor` (hipSYCL
+  and DPC++ only) and `group` functions. (2588d7e)
+- Add support for SYCL 2020-style reductions (hipSYCL with required patch, DPC++
+  partially, ComputeCpp unsupported). (e79f765)
+- Add support for DPC++ as a SYCL implementation. (44c181e)
+- The API for accessing distributed data from within host tasks (previously
+  known as `host_memory_layout`) is streamlined into a new
+  `buffer_allocation_window` API. (ad66329)
+- Add support for multi-dimensional subscript operators for host and device
+  accessors. (c720ffb)
+- Add support for SYCL 2020-style accessor constructors as well as new
+  `access_mode` and `target` enums. (c36f55e)
+
+### Changed
+
+- Celerity will now fall back to using any available SYCL devices instead of
+  aborting in case no GPUs can be found. (0d87461)
+- Improve performance of some applications with large task graphs. (1417296)
+- Rename `CELERITY_PROFILE_OCL` to `CELERITY_PROFILE_KERNEL`. (ae94ef4)
+- Improve handling of configuration environment variables such as
+  `CELERITY_DEVICES`. (fc595d2)
+- Terminate execution in case an asynchronous SYCL error is reported. (10d3d75)
+- Remove dependency on Boost. (ae66f22)
+- Report an error when more than one build configuration (Debug, Release, ...)
+  of Celerity is installed to the same location. (2c12944)
+
+### Deprecated
+
+- `host_memory_layout` and associated functions are being deprecated in favor of
+  `buffer_allocation_window`. (ad66329)
+- Range mappers no longer require kernel and buffer dimensions to be explicitly
+  specified. Doing so will now trigger a deprecation warning. (50dd62d)
+
+### Removed
+
+- Remove support for `CELERITY_FORCE_WG` configuration environment variable.
+  (afe81cc)
+
+### Fixed
+
+- Fix a crash occurring when creating new buffers after a number of tasks have
+  already been processed. (d33c8d2)
+- Forward correct offset / range to SYCL accessors internally. (349d58b)
+- Fix a crash that could happen when building a Debug executable against a
+  Release installation of Celerity or vice-versa. (2c12944)
+- Fix a bug that could cause nested SYCL command groups to be submitted. (750b28a)
+
 ## [0.2.1] - 2020-09-09
 
 ### Fixed
@@ -52,4 +114,4 @@ Versioning](http://semver.org/spec/v2.0.0.html).
 
 ## [0.1.0] - 2019-09-05
 
-__Hello, World!__ This is our first release!
+**Hello, World!** This is our first release!