Update colorlog to 3.1.0

[pyup-bot]

There's a new version of colorlog available.
You are currently using 2.6.0. I have updated it to 3.1.0

These links might come in handy: PyPI | Changelog | Repo

Changelog

3.1.0

This removed the use of parse_colors directly in format strings, as it relied on an implementation specific detail of Python 2 and was broken on Python 3 (i.e. setting __missing__ on an object's __dict__). It also adds some usage examples.

2.7.0

Adds a level based formatter - thanks mdraw! (borntyping/python-colorlog#32)

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖

[codecov]

Codecov Report

Merging #2888 into develop will decrease coverage by 20.64%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##           develop    #2888       +/-   ##
============================================
- Coverage    76.06%   55.41%   -20.65%     
============================================
  Files          186       10      -176     
  Lines         7277      545     -6732     
  Branches       915      146      -769     
============================================
- Hits          5535      302     -5233     
+ Misses        1563      243     -1320     
+ Partials       179        0      -179

Impacted Files	Coverage Δ
kolibri/content/utils/channels.py
...libri/content/management/commands/importchannel.py
...e/discovery/management/commands/enumeratedrives.py
kolibri/content/utils/annotation.py
kolibri/core/views.py
kolibri/plugins/user/hooks.py
kolibri/__main__.py
kolibri/core/device/serializers.py
kolibri/core/mixins.py
kolibri/plugins/style_guide/kolibri_plugin.py
... and 167 more

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[benjaoming]

The LevelFormatter is potentially interesting, doesn't seem like a risky change. They also added Python 3.5 support..

octocat/linguist@v2.2.0...octocat:v2.3.3