bump travis Julia version

Author: aviatesk

.travis.yml

@@ -1,7 +1,7 @@
 language: julia
 
 julia:
-  - 1.2
+  - 1.3
   - nightly
 
 env:
@@ -20,11 +20,11 @@ matrix:
   include:
     # # Sanity check for OS X
     # - os: osx
-    #   julia: 1.2
+    #   julia: 1.3
     #   env: ATOMJL=master
     # Sanity check for Atom Beta
     - os: linux
-      julia: 1.2
+      julia: 1.3
       env: ATOM_CHANNEL=beta
   allow_failures:
     - julia: nightly