Update flask-admin to 1.6.0

[pyup-bot]

This PR updates flask-admin from 1.5.1 to 1.6.0.

Changelog

1.6.0

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* Dropped Python 2 support
* WTForms 3.0 support
* Various fixes

1.5.8

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* SQLAlchemy 1.4.5+ compatibility fixes
* Redis CLI fixes

1.5.7

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* Bootstrap 4 support!
* Added hook for custom SQLAlchemy models initializers
* SQLAlchemy 1.4/2.0 compatibility fix

1.5.6

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* SQLAlchemy 1.3.6 compatibility fix
* Python 3.8 support

1.5.5

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* Werkzeug 1.0 compatibility fix
* Use fa-circle-o icon for unchecked booleans
* A few SQLAlchemy-related bug fixes

1.5.4

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* Fix display of inline x-editable boolean fields on list view
* Add support for several SQLAlchemy-Utils data types
* Support searching on SQLAlchemy hybrid properties
* Extra URL paramaters are now propagated to the next page when searching / filtering
* Add enum34 dependency when running on legacy Python version
* Update Mapbox API v1 URL format
* Update jQuery and moment dependencies in templates
* Fixed a datepicker issue, where only dates up to 2015 were showing up
* Updated Pillow dependency version

1.5.3

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* Fixed XSS vulnerability
* Support nested categories in the navbar menu
* SQLAlchemy
 * sort on multiple columns with `column_default_sort`
 * sort on related models in `column_sortable_list`
 * show searchable fields in search input's placeholder text
 * fix: inline model forms can now also be used for models with multiple primary keys
 * support for using mapped `column_property`
* Upgrade Leaflet and Leaflet.draw plugins, used for geoalchemy integration
* Specify `minimum_input_length` for ajax widget
* Peewee: support composite keys
* MongoEngine: when searching/filtering the input is now regarded as case-insensitive by default
* FileAdmin
 * handle special characters in filename
 * fix a bug with listing directories on Windows
 * avoid raising an exception when unknown sort parameter is encountered
* WTForms 3 support

1.5.2

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* Fixed XSS vulnerability
* Fixed Peewee support
* Added detail view column formatters
* Updated Flask-Login example to work with the newer version of the library
* Various SQLAlchemy-related fixes
* Various Windows related fixes for the file admin

Links

• PyPI: https://pypi.org/project/flask-admin
• Changelog: https://pyup.io/changelogs/flask-admin/
• Repo: https://github.com/flask-admin/flask-admin/
• Docs: https://pythonhosted.org/Flask-Admin/