Updated changelog

Author: lazychaser

CHANGELOG.markdown

@@ -7,7 +7,7 @@
     -   `insertAfter` to `insertAfterNode`
     -   `getNext` to `getNextNode`
     -   `getPrev` to `getPrevNode`
-*   #82: Fixing tree now handles case when nodes pointing non-existing parent
+*   #82: Fixing tree now handles case when nodes pointing to non-existing parent
 *   The number of missing parent is now returned when using `countErrors`
 *   #79: implemented scoping feature
 *   #81: moving node now makes model dirty before saving it
@@ -17,6 +17,7 @@
 *   Default order is no longer applied for `siblings()`, `descendants()`,
     `prevNodes`, `nextNodes`
 *   #50: implemented tree rebuilding feature
+*   #85: added tree flattening feature
 
 ### 3.1.1