NFS cleanup no longer errors if /etc/exports doesn't exist. [closes GH-126]

CHANGELOG.md

@@ -1,5 +1,7 @@
 ## 0.5.1 (unreleased)
 
+  - Fixed NFS erroring when NFS wasn't even enabled if `/etc/exports` doesn't
+    exist. [GH-126]
   - Fixed `vagrant resume` to properly resume a suspended VM. [GH-122]
   - Fixed `halt`, `destroy`, `reload` to where they failed if the VM was
     in a saved state. [GH-123]

lib/vagrant/hosts/bsd.rb

@@ -40,6 +40,7 @@ module Vagrant
       end
 
       def nfs_cleanup
+        return if !File.exist?("/etc/exports")
         system("cat /etc/exports | grep 'VAGRANT-BEGIN: #{env.vm.uuid}' > /dev/null 2>&1")
 
         if $?.to_i == 0

lib/vagrant/hosts/linux.rb

@@ -39,6 +39,7 @@ module Vagrant
       end
 
       def nfs_cleanup
+        return if !File.exist?("/etc/exports")
         system("cat /etc/exports | grep 'VAGRANT-BEGIN: #{env.vm.uuid}' > /dev/null 2>&1")
 
         if $?.to_i == 0