Update changelog.

Author: Nikita Manovich

CHANGELOG.md

@@ -4,19 +4,13 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [1.0.0-beta.2] - Unreleased
+## [1.0.0-beta.2] - 2020-04-30
 ### Added
 - Re-Identification algorithm to merging bounding boxes automatically to the new UI (<https://github.com/opencv/cvat/pull/1406>)
 - Methods ``import`` and ``export`` to import/export raw annotations for Job and Task in ``cvat-core`` (<https://github.com/opencv/cvat/pull/1406>)
 - Versioning of client packages (``cvat-core``, ``cvat-canvas``, ``cvat-ui``). Initial versions are set to 1.0.0  (<https://github.com/opencv/cvat/pull/1448>)
 - Cuboids feature was migrated from old UI to new one. (<https://github.com/opencv/cvat/pull/1451>)
 
-### Changed
--
-
-### Deprecated
--
-
 ### Removed
 - Annotation convertation utils, currently supported natively via Datumaro framework (https://github.com/opencv/cvat/pull/1477)
 
@@ -36,9 +30,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Fix apache startup after PC restart (https://github.com/opencv/cvat/pull/1467)
 - Open task button doesn't work (https://github.com/opencv/cvat/pull/1474)
 
-### Security
--
-
 ## [1.0.0-beta.1] - 2020-04-15
 ### Added
 - Special behaviour for attribute value ``__undefined__`` (invisibility, no shortcuts to be set in AAM)