Change sbt installation

Author: jllopes

circle.yml

@@ -1,6 +1,9 @@
 machine:
   pre:
-    - mkdir -p $HOME/.sbt/.lib/1.1.6 && wget http://central.maven.org/maven2/org/scala-sbt/sbt-launch/1.1.6/sbt-launch-1.1.6.jar -O $HOME/.sbt/.lib/1.1.6/sbt-launch.jar
+    - echo "deb https://dl.bintray.com/sbt/debian /" | sudo tee -a /etc/apt/sources.list.d/sbt.list
+    - sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv 2EE0EA64E40A89B84B2DF73499E82A75642AC823
+    - sudo apt-get -y update
+    - sudo apt-get -y install sbt
   java:
     version: oraclejdk8