adds golang 1.11.x and tip to build

Signed-off-by: Mike Brown <brownwm@us.ibm.com>

.travis.yml

@@ -2,48 +2,48 @@ git:
   depth: 150
 
 language: go
+go:
+  - 1.11.x
+  - tip
+
+matrix:
+  allow_failures:
+    - go: tip
 
 sudo: required
 
 services:
-    - docker
+  - docker
 
 cache:
-    directories:
-        - "${HOME}/google-cloud-sdk/"
+  directories:
+    - "${HOME}/google-cloud-sdk/"
 
 before_install:
-    # libseccomp in trusty is not new enough, need backports version.
-    - sudo sh -c "echo 'deb http://archive.ubuntu.com/ubuntu trusty-backports main restricted universe multiverse' > /etc/apt/sources.list.d/backports.list"
-    - sudo apt-get update
+  # libseccomp in trusty is not new enough, need backports version.
+  - sudo sh -c "echo 'deb http://archive.ubuntu.com/ubuntu trusty-backports main restricted universe multiverse' > /etc/apt/sources.list.d/backports.list"
+  - sudo apt-get update
 
 install:
-    - sudo apt-get install btrfs-tools
-    - sudo apt-get install libseccomp2/trusty-backports
-    - sudo apt-get install libseccomp-dev/trusty-backports
-    - sudo apt-get install socat
+  - sudo apt-get install btrfs-tools
+  - sudo apt-get install libseccomp2/trusty-backports
+  - sudo apt-get install libseccomp-dev/trusty-backports
+  - sudo apt-get install socat
 
 before_script:
-    - export PATH=$HOME/gopath/bin:$PATH
+  - export PATH=$HOME/gopath/bin:$PATH
 
-jobs:
-  include:
-    - stage: Build
-      script:
-        - make install.tools
-        - make .gitvalidation
-        - make binaries
-      go: "1.10.x"
-    - stage: Test
-      script:
-        - make install.deps
-        - make containerd
-        - sudo PATH=$PATH GOPATH=$GOPATH make install-containerd
-        - make test
-        - make test-integration
-        - make test-cri
-      after_script:
-        # Abuse travis to preserve the log.
-        - cat /tmp/test-integration/containerd.log
-        - cat /tmp/test-cri/containerd.log
-      go: "1.10.x"
+script:
+  - make install.tools
+  - make .gitvalidation
+  - make binaries
+  - make install.deps
+  - make containerd
+  - sudo PATH=$PATH GOPATH=$GOPATH make install-containerd
+  - make test
+  - make test-integration
+  - make test-cri
+after_script:
+  # Abuse travis to preserve the log.
+  - cat /tmp/test-integration/containerd.log
+  - cat /tmp/test-cri/containerd.log