display kernel info in CI

.travis.yml

@@ -6,6 +6,7 @@ go_import_path: v2ray.com/core
 git:
   depth: 5
 before_script:
+- uname -a
 - sudo ntpdate -u time.google.com
 - date
 script:

shippable.yml

@@ -10,6 +10,7 @@ branches:
 
 build:
   ci:
+    - uname -a
     - curl -L -o golang.tar.gz https://dl.google.com/go/go1.11.linux-arm64.tar.gz
     - tar -C /usr/local -xzf golang.tar.gz
     - export PATH=$PATH:/usr/local/go/bin