fixed warnings on travisci config

- root: deprecated key sudo (The key `sudo` has no effect anymore.)
- deploy: deprecated key skip_cleanup (not supported in dpl v2, use cleanup)

Signed-off-by: Avelino <t@avelino.xxx>

.travis.yml

@@ -3,8 +3,6 @@ language: go
 go:
   - 1.x
 
-sudo: false
-
 install:
   - go get -t -v ./...
 
@@ -16,6 +14,5 @@ before_deploy:
 deploy:
   provider: script
   script: netlify deploy --dir=tmpl --prod
-  skip_cleanup: true
   on:
     branch: master