Rejig Elixir and OTP versions in build

Use Elixir 1.2 and OTP 18.2, remove Elixir 1.0.5

Author: Josh Price

.travis.yml

@@ -1,7 +1,11 @@
 language: elixir
 elixir:
-  - 1.0.5
-  - 1.1.1
+  - 1.1
 otp_release:
   - 17.5
-  - 18.1
+  - 18.2
+
+matrix:
+  include:
+    - elixir: 1.2
+      otp_release: 18.2