We no longer use travis so removing configuration

Fixes #1846.

.travis.yml

@@ -1,34 +0,0 @@
-sudo: false
-cache:
-  directories:
-    - $HOME/.m2
-language: java
-jdk:
-  - oraclejdk8
-services:
-  - rabbitmq
-before_install:
-  - git config user.name "$GIT_NAME"
-  - git config user.email "$GIT_EMAIL"
-  - git config credential.helper "store --file=.git/credentials"
-  - echo "https://$GH_TOKEN:@github.com" > .git/credentials
-  - gem install asciidoctor
-install:
-- ./mvnw install -P docs -q -U -DskipTests=true $MVN_LOCAL_OPTS
-- '[ "${MVN_GOAL}" == "deploy" ] && ./docs/src/main/asciidoc/ghpages.sh || echo "Not updating docs"'
-script:
-- './mvnw -s .settings.xml $MVN_GOAL $MVN_PROFILE -nsu $MVN_LOCAL_OPTS'
-env:
-  global:
-  - MVN_LOCAL_OPTS="-Dmaven.source.skip=true -Dmaven.javadoc.skip=true -Dmaven.test.redirectTestOutputToFile=true"
-  - GIT_NAME="Dave Syer"
-  - GIT_EMAIL=dsyer@pivotal.io
-  - CI_DEPLOY_USERNAME=buildmaster
-  - FEATURE_BRANCH=$(echo ${TRAVIS_BRANCH} | grep -q "^.*/.*$" && echo true || echo false)
-  - SPRING_CLOUD_BUILD=$(echo ${TRAVIS_REPO_SLUG} | grep -q "^spring-cloud/.*$" && echo true || echo false)
-  - MVN_GOAL=install
-  - VERSION=$(mvn validate | grep Building | head -1 | sed -e 's/.* //')
-  - MILESTONE=$(echo ${VERSION} | egrep 'M|RC' && echo true || echo false)
-  - MVN_PROFILE=$([ "${MILESTONE}" == "true" ] && echo -P milestone)
-  - JAVA_OPTS="-Xmx1024m -XX:CICompilerCount=1 -XX:TieredStopAtLevel=1 -Djava.security.egd=file:/dev/./urandom"
-  - secure: aeLXRC5oFSddwnZt1/7G2/OHr7jDbxz0ET7sej3I+eSbe3N5vbzQ6FC08es4l89l54ciXd90I1g2BMw7DTYKOO373FP78XPdAEbifJTU4DGd6fCELmoTtUPhjunBIk7E49hisPbv82892IYYA7qi/hzG548cPyZ1IgiJjq0NCsc=