travis: Removed travis.yml.

Removed travis.yml in the process of shifting production tests
to CircleCI.

.travis.yml

@@ -1,66 +0,0 @@
-# See https://zulip.readthedocs.io/en/latest/testing/continuous-integration.html for
-# high-level documentation on our Travis CI setup.
-dist: xenial
-install:
-  # Disable sometimes-broken sources.list in Travis base images
-  - sudo rm -vf /etc/apt/sources.list.d/*
-  - sudo apt-get update
-
-  # Disable Travis CI's built-in NVM installation
-  - mispipe "mv ~/.nvm ~/.travis-nvm-disabled" ts
-
-  # Install codecov, the library for the code coverage reporting tool we use
-  # With a retry to minimize impact of transient networking errors.
-  - mispipe "pip install codecov" ts || mispipe "pip install codecov" ts
-
-  # This is the main setup job for the test suite
-  - mispipe "tools/ci/setup-$TEST_SUITE" ts
-
-  # Clean any caches that are not in use to avoid our cache
-  # becoming huge.
-  - mispipe "scripts/lib/clean-unused-caches --verbose --threshold 0" ts
-
-script:
-  # We unset GEM_PATH here as a hack to work around Travis CI having
-  # broken running their system puppet with Ruby.  See
-  # https://travis-ci.org/zulip/zulip/jobs/240120991 for an example traceback.
-  - unset GEM_PATH
-  - mispipe "./tools/ci/$TEST_SUITE" ts
-cache:
-  yarn: true
-  apt: false
-  directories:
-    - $HOME/zulip-venv-cache
-    - $HOME/zulip-npm-cache
-    - $HOME/zulip-emoji-cache
-    - $HOME/node
-    - $HOME/misc
-env:
-  global:
-    - BOTO_CONFIG=/nonexistent
-language: python
-# Our test suites generally run on Python 3.5, the version in
-# Ubuntu 16.04 xenial, which is the oldest OS release we support.
-matrix:
-  include:
-    # Travis will actually run the jobs in the order they're listed here;
-    # that doesn't seem to be documented, but it's what we see empirically.
-    # We only get 4 jobs running at a time, so we try to make the first few
-    # the most likely to break.
-    - python: "3.5"
-      env: TEST_SUITE=production
-    # Other suites moved to CircleCI -- see .circleci/.
-sudo: required
-addons:
-  artifacts:
-    paths:
-      # Casper debugging data (screenshots, etc.) is super useful for
-      # debugging test flakes.
-      - $(ls var/casper/* | tr "\n" ":")
-      - $(ls /tmp/zulip-test-event-log/* | tr "\n" ":")
-  postgresql: "9.5"
-  apt:
-    packages:
-      - moreutils
-after_success:
-  - codecov