--------------------
* The GlueApplication.add_data and load_data methods now return the
loaded data objects. [1239]
* Change default name of subsets to include the word 'Subset'. [1234]
* Removed ginga plugin from core package and moved it to a separate repository
at https://github.com/ejeschke/glue-ginga.
* Switch from using bundled WCSAxes to using the version in Astropy, and fixed
an issue that caused the frame of the axes to be too thick. [1231]
* Make it possible to define a default index for DataComboHelper - this makes
it possible for viewers to have three DataComboHelper and ensure that they
default to different attributes. [1163]
* Deal properly with adding Subset objects to DataComboHelper. [1163]
* Added the ability to export data and subset from the data collection view via
contextual menus. It was previously possible to export only the mask itself,
and only to FITS files, but the framework for exporting data/subsets has now
been generalized.
* When hiding layers in the RGB image viewer, make sure the current layer changes
to be a visible one if possible.
* Avoid merging IDs when creating identity links. The previous behavior of
merging was good for performance but made it impossible to undo the linking by
un-glueing. Derived components created by links are now hidden by default.
Finally, ``ComponentID`` objects now hold a reference to the first parent data
they are used in. [1189]
* Added a decorator that can be used to avoid circular calling of methods (can
occur when dealing with callbacks). [1207]
* Drop support for IPython 3.x and below, and make IPython and qtconsole into
required dependencies. [1145]
* Added new classes that can be used to hold the state of e.g. viewers and other
objects. These classes allow callbacks to be attached to various properties,
and can be used to define logical relations between different attributes
in a GUI-independent way.
* Fix selections when using Matplotlib 2.x, PyQt5 and a retina display. [1236]
* Updated ComponentIDComboHelper to no longer store ``(cid, data)`` as the
``userData`` but instead just the ``cid`` (the data is now accessible via
``cid.parent``). [1212]
* Avoid duplicate toolbar in dendrogram viewer. [1213, 1237]
* Fixed bug that caused the contrast to change for the incorrect layer in the
RGB image viewer.
* Fixed bug that caused coordinate information to be lost when merging datasets.
The original behavior of keeping the coordinate information from the first
dataset has been restored. [1186]
* Fix Data.update_values_from_data to make sure that original component order
is preserved. [1238]
* Fix Data.components to return original component order, not alphabetical order.
[1238]
* Fix significant performance bottlenecks with WCS coordinate conversions. [1185]
* Fix error when changing the contrast radio button the RGB image viewer mode,
and also fix bugs with setting the range of values manually. [1187]
* Fix a bug that caused coordinate axis labels to be lost during merging. [1195]
* Fix a bug that caused tab names to not be saved and restored to/from session
files. [1241, 1242]