drop OTP-17 from travis since it's too old for rebar3 to run tests
diff --git a/.travis.yml b/.travis.yml
index d2de56d..e1661f6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,8 +7,6 @@
   - 20.0
   - 19.3
   - 18.3
-  - 17.3
-  - 17.1
 script: "wget https://s3.amazonaws.com/rebar3/rebar3 && escript rebar3 do edoc, eunit, ct"
 branches:
   only: