change cache/network fetch behaviour of serviceworker.js

# Conflicts:
#	COPYRIGHT
#	README.md

# Conflicts:
#	schoolapps/dashboard/urls.py
#	schoolapps/dashboard/views.py
#	schoolapps/templates/partials/footer.html

Optimize design for dashboard (issue #321)

- Include React via babel compiler directly instead of using gulp/CRN…

Update serviceworker.js

don't cache login page

- Use production variantes of React, React DOM and Prop Types if not in debug mode (mentioned by @ZugBahnHof)

# Conflicts:
#	schoolapps/static/common/style.css

bugfix PWA caching

Merge/dashboard cache

# Conflicts:
#	.idea/misc.xml
#	requirements.txt
#	schoolapps/dashboard/urls.py
#	schoolapps/dashboard/views.py
#	schoolapps/schoolapps/settings.py
#	schoolapps/schoolapps/urls.py
#	schoolapps/templates/partials/header.html
#	schoolapps/timetable/views.py

Bump mixin-deep from 1.3.1 to 1.3.2 in /dynselect2

Bumps [mixin-deep](https://github.com/jonschlinkert/mixin-deep) from 1.3.1 to 1.3.2.
- [Release notes](https://github.com/jonschlinkert/mixin-deep/releases)
- [Commits](https://github.com/jonschlinkert/mixin-deep/compare/1.3.1...1.3.2

)

Signed-off-by: dependabot[bot] <support@github.com>

Feature/pwa optimization

# Conflicts:
#	schoolapps/dashboard/views.py
#	schoolapps/schoolapps/settings.py
#	schoolapps/schoolapps/urls.py
#	schoolapps/templates/common/404.html

Bugfix/show logged in notice again

Bugfix/404