Update travis

.Rbuildignore

@@ -5,3 +5,4 @@
 ^.travis.yml$
 ^appveyor.yml$
 ^revdep$
+^\.travis\.yml$

.travis.yml

@@ -1,31 +1,5 @@
-## Sample .travis.yml file for use with metacran/r-builder
-## See https://github.com/metacran/r-builder for details.
-
-language: c
-sudo: required
-
-before_install:
-  - curl -OL https://raw.githubusercontent.com/metacran/r-builder/master/pkg-build.sh
-  - chmod 755 pkg-build.sh
-  - ./pkg-build.sh bootstrap
-
-install:
-  - ./pkg-build.sh install_deps
-
-script:
-  - ./pkg-build.sh run_tests
-
-after_failure:
-  - ./pkg-build.sh dump_logs
-
-notifications:
-  email:
-    on_success: change
-    on_failure: change
-
-env:
-  matrix:
-    - RVERSION=oldrel
-    - RVERSION=release
-    - RVERSION=devel
+# R for travis: see documentation at https://docs.travis-ci.com/user/languages/r
 
+language: R
+sudo: false
+cache: packages