Replace Travis with GitHub actions and fix many typos (#1657)

* Create django.yml

* Fix working directory

* ..

* .

* ..

* a.

* ..

* .

* Fix typo

* Install hunspell

* maxfail

* Fix install

* .

* Reduce number of typos

* Even less typos

* Postgres debug

* Spelling fixes, yet again

* Postgres with PW

* Fix failing test

* New workflows

* Fix syntax error

* Install gettext

* Test aginst python 3.6 as well

* Clean up strategies

* Add badge, do not ignore migrations

* Use pip cache

src/pretix/control/templates/pretixcontrol/items/quotas.html

@@ -8,7 +8,7 @@
             To make your products actually available, you also need quotas. Quotas define, how many instances of
             your product pretix will sell. This way, you can configure whether your event can take an unlimited
             number of attendees or the number of attendees is limited. You can assign a product to multiple quotas
-            to fulfil more complex requirements, e.g. if you want to limit the total number of tickets sold and the
+            to fulfill more complex requirements, e.g. if you want to limit the total number of tickets sold and the
             number of a specific ticket type at the same time.
         {% endblocktrans %}
     </p>