ci: Remove Travis CI

- Replace travis-ci's badge with circle-ci's badge in README
- Remove .travis.yml
- Remove requirements.txt

Signed-off-by: Joseph Nuthalapati <njoseph@thoughtworks.com>
Reviewed-by: James Valleroy <jvalleroy@mailbox.org>

.travis.yml

@@ -1,34 +0,0 @@
-# Travis-CI configuration file for Plinth
-
-dist: trusty
-sudo: required
-language: generic
-
-env:
-  - DJANGO_VERSION=">=1.11.0"
-
-# Debian packages required
-before_install:
-  - sudo apt-get update -qq
-  - sudo apt-get -y install augeas-tools python3-dev python3-gi libaugeas-dev python3-configobj
-
-# Command to install dependencies
-install:
-  - virtualenv --python=/usr/bin/python3 --system-site-packages _venv
-  - source _venv/bin/activate
-  - pip install Django$DJANGO_VERSION
-  - pip install coverage==3.7
-  - pip install -r requirements.txt
-
-# Command to run tests
-script: python3 setup.py test
-
-notifications:
-  email:
-    on_success: change
-    on_failure: always
-  irc:
-    channels:
-      - "irc.oftc.net#freedombox-ci"
-    on_success: always
-    on_failure: always

README.md

@@ -1,5 +1,4 @@
-[![Build Status](https://travis-ci.org/freedombox/Plinth.svg?branch=master)](https://travis-ci.org/freedombox/Plinth)
-[![CircleCI](https://circleci.com/gh/freedombox/Plinth.svg?style=svg)](https://circleci.com/gh/freedombox/Plinth)
+[![Build Status](https://circleci.com/gh/freedombox/Plinth.svg?branch=master)](https://circleci.com/gh/freedombox/Plinth)
 [![Translation status](https://hosted.weblate.org/widgets/freedombox/-/shields-badge.svg)](https://hosted.weblate.org/engage/freedombox/?utm_source=widget)
 [![Debian Unstable](https://badges.debian.net/badges/debian/unstable/plinth/version.svg)](https://packages.debian.org/unstable/plinth)
 [![Debian Testing](https://badges.debian.net/badges/debian/testing/plinth/version.svg)](https://packages.debian.org/testing/plinth)

requirements.txt

@@ -1,13 +0,0 @@
-cherrypy >= 3.0
-configobj
-coverage >= 3.7
-django >= 1.11.0
-django-axes
-django-bootstrap-form
-django-simple-captcha
-django-stronghold
-psutil
-python-apt
-python-augeas
-requests
-ruamel.yaml