Merge pull request #32 from plastic-forks/zd/improve-doc

Improve docs and fix a warning

guides/introduction/Tracking columns and using labels.md

@@ -36,18 +36,18 @@ You can also use labels in general without tracking specific columns:
    pub_sub: MyApp.PubSub,
    watchers: [
      # ...
-     {User, :updated, label: :user_update},
+     {User, :updated, label: :user_updated},
      # ...
    ]}
 
   # subscribing
-  EctoWatch.subscribe(:user_update)
+  EctoWatch.subscribe(:user_updated)
   # or...
-  EctoWatch.subscribe(:user_update, package.id)
+  EctoWatch.subscribe(:user_updated, package.id)
   # or...
-  EctoWatch.subscribe(:user_update, {:role_id, role_id})
+  EctoWatch.subscribe(:user_updated, {:role_id, role_id})
 
   # handling messages
-  def handle_info({:user_update, %{id: id}}, socket) do
+  def handle_info({:user_updated, %{id: id}}, socket) do
 ```
 

lib/ecto_watch.ex

@@ -41,7 +41,6 @@ defmodule EctoWatch do
     Supervisor.init(children, strategy: :rest_for_one)
   end
 
-  @since "0.8.0"
   @deprecated "subscribe/3 was removed in version 0.8.0. See the updated documentation"
   def subscribe(schema_mod_or_label, update_type, id) when is_atom(schema_mod_or_label) do
     if Helpers.ecto_schema_mod?(schema_mod_or_label) do