Upgrade Kubernetes default version to 1.7.4.

Signed-off-by: Paulo Pires <pjpires@gmail.com>

Author: pires

README.md

@@ -127,7 +127,7 @@ Most aspects of your cluster setup can be customized with environment variables.
 
  - **KUBERNETES_VERSION** defines the specific kubernetes version being used.
 
-   Defaults to `1.7.3`.
+   Defaults to `1.7.4`.
    Versions prior to `1.7.0` **won't work** with current cloud-config files.
 
  - **USE_KUBE_UI** defines whether to deploy or not the Kubernetes UI

Vagrantfile

@@ -75,7 +75,7 @@ DOCKERCFG = File.expand_path(ENV['DOCKERCFG'] || "~/.dockercfg")
 
 DOCKER_OPTIONS = ENV['DOCKER_OPTIONS'] || ''
 
-KUBERNETES_VERSION = ENV['KUBERNETES_VERSION'] || '1.7.3'
+KUBERNETES_VERSION = ENV['KUBERNETES_VERSION'] || '1.7.4'
 
 CHANNEL = ENV['CHANNEL'] || 'alpha'
 #if CHANNEL != 'alpha'