Merge branch 'devel' into devel

docs/source/api/reactive-dict.md

@@ -91,6 +91,8 @@ Template.main.events({
 // Clicking the button will change the page to say "We've always been at war with Eurasia"
 ```
 
+{% apibox "ReactiveDict#delete" %}
+
 {% apibox "ReactiveDict#equals" %}
 
 If value is a scalar, then these two expressions do the same thing:

guide/source/2.12-migration.md

@@ -25,6 +25,9 @@ It will run your app and every time you use the old API, you will see a warning
 in your console. This will help you find the places in your code that need to
 be updated.
 
+If you are in doubt whether a particular API is old or new, you can check our [v2.8 migration](https://guide.meteor.com/v2.10/2.8-migration.html) guide
+that lists all the changes in the new API.
+
 <h2 id="older-versions">Migrating from a version older than 2.11?</h2>
 
 If you're migrating from a version of Meteor older than Meteor 2.11, there may