Register fedora host as CentOS too [GH-1394]

CHANGELOG.md

@@ -21,6 +21,7 @@ BUG FIXES:
   - NFS export allows access from all private networks on the VM. [GH-1204]
   - Default VirtualBox VM name now contains the machine name as defined
     in the Vagrantfile, helping differentiate multi-VM. [GH-1281]
+  - NFS works properly on CentOS hosts. [GH-1394]
 
 ## 1.2.4 (July 16, 2013)
 

plugins/hosts/fedora/host.rb

@@ -12,7 +12,9 @@ module VagrantPlugins
 
         if release_file.exist?
           release_file.open("r") do |f|
-            return true if f.gets =~ /^Fedora/
+            contents = f.gets
+            return true if contents =~ /^Fedora/
+            return true if contents =~ /^CentOS/
           end
         end