Setup ci with Travis (#9)

Author: stankoua

.ci_scripts/validate.sh

@@ -0,0 +1,18 @@
+#! /bin/bash
+
+set -e
+
+echo "[INFO] Check the source format"
+
+sbt ++$TRAVIS_SCALA_VERSION scalafmt test:scalafmt > /dev/null
+git diff --exit-code || (cat >> /dev/stdout <<EOF
+[ERROR] Scalafmt check failed, see differences above.
+To fix, format your sources using sbt scalafmt test:scalafmt before submitting a pull request.
+Additionally, please squash your commits (eg, use git commit --amend) if you're going to update this pull request.
+EOF
+false
+)
+
+echo "[INFO] Running tests" >> /dev/stdout
+
+sbt ++$TRAVIS_SCALA_VERSION testOnly

.travis.yml

@@ -0,0 +1,10 @@
+sudo: false
+language: scala
+jdk:
+  - oraclejdk8
+scala: 2.12.4
+cache:
+  directories:
+  - $HOME/.ivy2
+  - $HOME/.sbt
+script: ./.ci_scripts/validate.sh