Fix readthedocs config, fix CI badge

.readthedocs.yml

@@ -0,0 +1,18 @@
+# .readthedocs.yml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Build documentation in the docs/ directory with Sphinx
+sphinx:
+  configuration: docs/conf.py
+
+# Optionally set the version of Python and requirements required to build your docs
+python:
+  version: 3.7
+  install:
+    - requirements: docs/requirements.txt
+    - method: pip
+      path: .

README.md

@@ -1,6 +1,6 @@
 # django-bootstrap3
 
-[![Build](https://travis-ci.org/zostera/django-bootstrap3.svg?branch=main)](https://travis-ci.org/zostera/django-bootstrap3)
+[![CI](https://github.com/zostera/django-bootstrap3/workflows/CI/badge.svg?branch=main)](https://github.com/zostera/django-bootstrap3/actions?workflow=CI)
 [![Coverage Status](https://coveralls.io/repos/github/zostera/django-bootstrap3/badge.svg?branch=main)](https://coveralls.io/github/zostera/django-bootstrap3?branch=main)
 [![Latest PyPI version](https://img.shields.io/pypi/v/django-bootstrap3.svg)](https://pypi.python.org/pypi/django-bootstrap3)
 [![Any color you like](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/ambv/black)