When specifying NFS synced folders we need to use a symbol (fix GH-76)

CHANGELOG.md

@@ -5,7 +5,7 @@ BACKWARDS INCOMPATIBILITY:
   - Automatic handling of multiple machine scoped cache dirs from versions
     prior to 0.3.0 of this plugin was removed.
   - Support for `enable_nfs` has been deprecated and will be removed on 0.7.0,
-    please use `cache.synced_folder_opts = {type: 'nfs'}` instead.
+    please use `cache.synced_folder_opts = {type: :nfs}` instead.
 
 FEATURES:
 

README.md

@@ -31,7 +31,7 @@ Vagrant.configure("2") do |config|
     # shared folders. This is also very useful for vagrant-libvirt if you want
     # bi-directional sync
     config.cache.synced_folder_opts = {
-      type: 'nfs',
+      type: :nfs,
       # The nolock option can be useful for an NFSv3 client that wants to avoid the
       # NLM sideband protocol. Without this option, apt-get might hang if it tries
       # to lock files needed for /var/cache/* operations. All of this can be avoided

docs/index.md

@@ -35,7 +35,7 @@ Vagrant.configure("2") do |config|
     # shared folders. This is also very useful for vagrant-libvirt if you want
     # bi-directional sync
     config.cache.synced_folder_opts = {
-      type: 'nfs',
+      type: :nfs,
       # The nolock option can be useful for an NFSv3 client that wants to avoid the
       # NLM sideband protocol. Without this option, apt-get might hang if it tries
       # to lock files needed for /var/cache/* operations. All of this can be avoided

docs/usage.md

@@ -6,7 +6,7 @@ This is the easiest way to get started with plugin. By adding the code below to
 your `Vagrantfile` you can enable automatic detection of supported cache _buckets_.
 It is a good practice to wrap plugin specific configuration with `has_plugin?` checks
 so the user's Vagrantfiles do not break if vagrant-cachier is uninstalled or
-the Vagrantfile is shared with people that do not have the plugin installed.
+the Vagrantfile is shared with people that don't have the plugin installed.
 
 ```ruby
 Vagrant.configure("2") do |config|
@@ -44,7 +44,7 @@ VirtualBox and want to enable NFS for improved performance:
 ```ruby
 Vagrant.configure("2") do |config|
   config.cache.synced_folder_opts = {
-    type: 'nfs',
+    type: :nfs,
     # The nolock option can be useful for an NFSv3 client that wants to avoid the
     # NLM sideband protocol. Without this option, apt-get might hang if it tries
     # to lock files needed for /var/cache/* operations. All of this can be avoided

lib/vagrant-cachier/config.rb

@@ -21,9 +21,9 @@ module VagrantPlugins
         # TODO: Show warning!!!
         @ui.warn "The `enable_nfs` config for vagrant-cachier has been deprecated " \
                 "and will be removed on 0.7.0, please use " \
-                "`synced_folder_opts = { type: 'nfs' }` instead.\n"
+                "`synced_folder_opts = { type: :nfs }` instead.\n"
 
-        @synced_folder_opts = { type: 'nfs', nfs: true } if value
+        @synced_folder_opts = { type: :nfs } if value
       end
 
       def validate(machine)