switch to version 2.14.0, update changelog

move the bookmark validation logic into the model, as well as the
bookmark to root code

doc/NERD_tree.txt

@@ -202,6 +202,8 @@ double-click.......same as the |NERDTree-o| map.
 middle-click.......same as |NERDTree-tab| for files, same as
                    |NERDTree-e| for dirs.
 
+D.......Delete the current bookmark .............................|NERDTree-D|
+
 P.......Jump to the root node....................................|NERDTree-P|
 p.......Jump to current nodes parent.............................|NERDTree-p|
 K.......Jump up inside directories at the current tree depth.....|NERDTree-K|
@@ -342,6 +344,14 @@ Applies to: files and directories.
 
 Opens a netrw on the selected directory, or the selected file's directory.
 
+------------------------------------------------------------------------------
+                                                                  *NERDTree-D*
+Default key: D
+Map option: NERDTreeMapDeleteBookmark
+Applies to: lines in the bookmarks table
+
+Deletes the currently selected bookmark.
+
 ------------------------------------------------------------------------------
                                                                   *NERDTree-P*
 Default key: P
@@ -889,6 +899,12 @@ fridge for later ;)
 ==============================================================================
 7. Changelog                                               *NERDTreeChangelog*
 
+2.14.0
+    - fix a bug where the <c-w>o mapping  would cause the tree window to be
+      incorrectly sized when reopened.
+    - add keymapping to delete bookmarks from the bookmarks table, see
+      :help NERDTree-D
+    - lots of refactoring
 2.13.0
     - make NERDTreeChDir option default to 0 (i.e. never change vims current
       working dir by default)