Libertem

Most prominently, this release features **full Dask array integration**. That means HyperSpy lazy signals and LiberTEM can now be combined seamlessly. Many thanks to Matthew Bryan who implemented major parts of this non-trivial feature!

This enables the following applications:

* Use HyperSpy file readers and other readers that create Dask arrays for LiberTEM.
* Create an ad-hoc file reader for LiberTEM by just building a Dask array from your input data.
* Use LiberTEM file readers for HyperSpy and other software that works with Dask arrays.
* Use the same implementation of an algorithm for live processing with LiberTEM, offline processing with LiberTEM, and offline processing with HyperSpy.
* Simplify implementation of complex processing routines on Dask arrays.
* Chain processing steps together using Dask arrays for intermediate results.

More details about Dask integration can be found at https://libertem.github.io/LiberTEM/dask.html.

Please note that these features are still experimental and cover a large space of possible uses and parameters. Expect the unexpected! Tests, feedback and improvements are highly appreciated.

Other improvements

* Support for TVIPS binary files
* Support for MIB Quad integer and some raw formats
* Parameter guessing for center of mass analysis
* I/O back-end selection and direct I/O, beneficial for very large data on fast SSDs
* Docker image available: https://hub.docker.com/r/libertem/libertem/tags
* Improved parameter handling and the new threaded `ConcurrentJobExecutor` speed up UDFs with large parameters, for example single side band ptychography.
* Various other performance and quality improvements

Please [see our changelog](https://libertem.github.io/LiberTEM/changelog.html#v0-9-0) for the full release notes with details on the changes and new features.

This release mainly contains improvements of center of mass / first moment analysis and support for starting the web GUI from JupyterHub or JupyterLab.

New features
* Support for center of mass with annular masks in `create_com_analysis()`, `COMAnalysis` and the GUI (633, 1089).

* Support in the GUI for specifying rotation of scan against detector and flipping the detector y axis (1087, 31). Previously this was only supported in the Python API.

* Tweaks and instructions for JupyterHub and JupyterLab integration in LiberTEM, see Jupyter integration (1074). New package [LiberTEM/LiberTEM-jupyter-proxy](https://github.com/LiberTEM/LiberTEM-jupyter-proxy) for interfacing.

* In the web API, support was added to re-run visualization only, without re-running UDFs for an analysis. This allows for almost instant feedback for some operations, like changing CoM parameters.

* Added token-based authentication. For now, it is only usable via integrations like Jupyter. It will be extended to local/manual usage later (1074, 1097). Please comment on 1097 if local/manual use would be beneficial for you so that it is prioritized accordingly.

* SEQ dataset: Added support for loading excluded pixels from XML (805, 1077). See `SEQDataSet` for more information. Also support both *.seq.seq and *.seq as extension for the main SEQ file to find files with matching base name that contain correction data (1120, 1121).

For the full release notes, please see [our changelog](https://libertem.github.io/LiberTEM/changelog.html#v0-8-0)