Merge pull request #1878 from atom/ks-mutate-selected-text-public

Make Editor::mutateSelectedText public

src/editor.coffee

@@ -1002,6 +1002,12 @@ class Editor extends Model
     deprecate("Use Editor::duplicateLines() instead")
     @duplicateLines()
 
+  # Public: Mutate the text of all the selections in a single transaction.
+  #
+  # All the changes made inside the given {Function} can be reverted with a
+  # single call to {::undo}.
+  #
+  # fn - A {Function} that will be called with each {Selection}.
   mutateSelectedText: (fn) ->
     @transact => fn(selection) for selection in @getSelections()