Added 2 Operations to Batch Methods to rest.rb
Added 2 Operations to Batch Methods to rest.rb

Modified the neography/rest.rb 'get_batch' to add a case for
 :remove_node_from_index
 :delete_node
Both method use the HTTP DELETE Methods and contain no 'body'

Did not account for alias :remove_node_index

Still need to add tests.

Autrement/neography,maxdemarzi/neography,andycamp/neography,agarbuno/neography