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* Major refactor of the job execution engine to use Trollius/Asyncio.
* Changed the way build environments are generated (no more ``build.sh``).
* Added new "Linked-devel" space option, where the ``devel`` space for each package is isolated, but are symlinked to a single merged ``devel`` space afterwards.
* Added support for cleaning and partial cleaning of the workspace with ``catkin clean``.
* Added "shell verbs" like ``catkin cd`` and ``catkin source`` (requires sourcing of shell files).
* Added support for (and testing for) ``DESTDIR``.
* Warnings are now captured and reported to the console even without ``--verbose``.
* Fixed ``setup.py`` installation when using ``--user``.
* Fixed an issue where CMake was always rerun even when the settings didn't change.
* Added support for the ``.built_by`` marker file to detect when being used at the same time as ``catkin_make[_isolated]``.
* Fixed ``catkin create -p``.
* Improved error message when a circular dependency in the packages is detected.
* Fixed a problem where ``catkin config`` could incorrectly clear the make arguments.
* Fixed a bug where the UI could get stuck on "calculating new jobs".
* Fixed a bug where the ``--isolated-devel`` option would crash when building a subset of the workspace.
* Fixed the "leaf_sources out of bounds" error.
* Moved log files out of ``build/logs`` into "log space" in the workspace root.
* Added `env` utility verb for querying environment and running commands in a modified environment.
* Build types (i.e. cmake, catkin) are now supplied through ``entry_points``.
* Added "environemnt caching" for build jobs to speed up building in some cases.
* Contributors: Alexander Schaefer, Dave Coleman, Dirk Thomas, Esteve Fernandez, Ivor Wanders, Jonathan Bohren, Kartik Mohta, Kei Okada, Kentaro Wada, Robert Haschke, Steven Peters, William Woodall