stop tests of centos 6.6 and 6.4 and updated image for centos 7

Author: steenzout

README.md

@@ -25,8 +25,6 @@ DISCLAIMER: usage of any version of this role implies you have accepted the
 | Debian | Ubuntu  | Trusty    | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
 | Debian | Ubuntu  | Vivid     | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
 | Debian | Ubuntu  | Wily      | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
-| RedHat | CentOS  | 6.4       | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
-| RedHat | CentOS  | 6.6       | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
 | RedHat | Centos  | 7         | [![x86_64](http://img.shields.io/badge/x86_64-passed-006400.svg?style=flat)](#) |
 
 ## Requirements

tests/boxes.yml

@@ -8,7 +8,7 @@ vagrant:
   # CentOS
 
   centos64-64.vagrant.dev:
-    enabled: true
+    enabled: false
     box: hansode/centos-6.4-x86_64
     network:
       name: private_network
@@ -20,7 +20,7 @@ vagrant:
         cpus: 1
 
   centos66-64.vagrant.dev:
-    enabled: true
+    enabled: false
     box: hansode/centos-6.6-x86_64
     network:
       name: private_network
@@ -33,7 +33,7 @@ vagrant:
 
   centos7-64.vagrant.dev:
     enabled: true
-    box: relativkreativ/centos-7-minimal
+    box: centos/7
     network:
       name: private_network
       ip: 192.168.121.3