Add support for "ansible.start_at_task" attribute

plugins/provisioners/ansible/config.rb

@@ -10,6 +10,7 @@ module VagrantPlugins
       attr_accessor :sudo_user
       attr_accessor :verbose
       attr_accessor :tags
+      attr_accessor :start_at_task
 
       # Joker attribute, used to pass unsupported arguments to ansible anyway
       attr_accessor :raw_arguments
@@ -24,6 +25,7 @@ module VagrantPlugins
         @sudo_user      = UNSET_VALUE
         @verbose        = UNSET_VALUE
         @tags           = UNSET_VALUE
+        @start_at_task  = UNSET_VALUE
         @raw_arguments  = UNSET_VALUE
       end
 
@@ -37,6 +39,7 @@ module VagrantPlugins
         @sudo_user      = nil if @sudo_user == UNSET_VALUE
         @verbose        = nil if @verbose == UNSET_VALUE
         @tags           = nil if @tags == UNSET_VALUE
+        @start_at_task  = nil if @start_at_task == UNSET_VALUE
         @raw_arguments  = nil if @raw_arguments == UNSET_VALUE
       end
 

plugins/provisioners/ansible/provisioner.rb

@@ -16,6 +16,7 @@ module VagrantPlugins
         options << "--ask-sudo-pass" if config.ask_sudo_pass
         options << "--tags=#{as_list_argument(config.tags)}" if config.tags
         options << "--limit=#{as_list_argument(config.limit)}" if config.limit
+        options << "--start-at-task=#{config.start_at_task}" if config.start_at_task
         options << "--sudo" if config.sudo
         options << "--sudo-user=#{config.sudo_user}" if config.sudo_user
         if config.verbose