Update Travis.yml

Author: nhaarman

.travis.yml

@@ -4,9 +4,9 @@ language: java
 
 matrix:
   include:
-  - jdk: oraclejdk7
+  - jdk: oraclejdk8
     env: TERM=dumb MOCK_MAKER=mock-maker-inline KOTLIN_VERSION=1.0.7
-  - jdk: oraclejdk7
+  - jdk: oraclejdk8
     env: TERM=dumb MOCK_MAKER=mock-maker-inline KOTLIN_VERSION=1.1.2-4
   - jdk: oraclejdk8
     env: TERM=dumb KOTLIN_VERSION=1.0.7