Updated Git branch "master" to "main".

Author: felixxm

.travis.yml

@@ -123,4 +123,4 @@ deploy:
   provider: script
   script: bash docker_push.sh $COMPOSE_APP
   on:
-    branch: master
+    branch: main

README.md

@@ -1,6 +1,6 @@
 # django-docker-box
 
-[![Build Status](https://travis-ci.org/django/django-docker-box.svg?branch=master)](https://travis-ci.org/django/django-docker-box)
+[![Build Status](https://travis-ci.org/django/django-docker-box.svg?branch=main)](https://travis-ci.org/django/django-docker-box)
 
 Run the django test suite across multiple databases.
 

docker-compose.yml

@@ -171,7 +171,7 @@ services:
     volumes:
     - /dev/shm:/dev/shm
 
-  # Firefox tests fail on master
+  # Firefox tests fail on main
   firefox:
     <<: *base
     command: --selenium=firefox --selenium-hub=http://firefox-browser:4444/wd/hub