Set filetype unconditionally and after defining mappings.

Because NERD_Tree sets the filetype in its buffer, it's tempting to hook into the FileType event in order to customize it. Unfortunately, the buffer-local mappings are only defined _after_ setting the filetype, so one cannot un-/redefine them via this mechanism. (I know there are config variables and an API for that, but one may have other unforeseen uses.)
Therefore, swap the order and set the filetype last. Also, use :setlocal filetype= instead of :setfiletype. In the (remote) chance that a custom filetype detection mistakenly sets a filetype for the NERD_Tree buffer, the :setfiletype would be without effect, but we want to force the filetype (for the special syntax) here.
Fix typo Casade to Cascade
Add correspoding close action to cascade open single child dir
Fixed typo in NERD_tree.txt
Fix help mistake
Create nested parent directories as needed

Allows the user to create or copy a nested node
in a single step with ma or mc, recursively
creating nested parent directories if needed, and
without throwing any errors if they already exist.

[Finishes #163, #34]
Ugly hack to fix Error 121 when NERDTree is the active window and clicking on the command line below another window.
Fix typo
Add option to respect wildignore
correct invalid reference to MenuController

I found an error when I tried to use [git_menu.vim](g:NERDTreeMenuController):

```
Error detected while processing function nerdtree#invokeKeyMap..91..90..<SNR>52_showMenu..65..82:
line    2:
E121: Undefined variable: s:MenuController
E15: Invalid expression: s:MenuController.New(self.children)
line    3:
E121: Undefined variable: mc
```

I searched the line at which it happened
then, I found that `s:MenuController` is not defined in  `menu_item.vim` but in menu_controller.vim .
So I corrected the name to refer to MenuController.
Issue 315 - Incorrect buffer deleted on file delete
Use pathogen.vim Helptags command in README file
Better support for bullet insertion and auto indentation in list items.
1. Added setlocal formatoptions-=c to disable automatically inserting bullets when auto-wrapping with textwidth.
2. Added indent/mkd.vim to support auto indent in list.
Merge pull request #70 from beyondwdq/master

Disable automatically inserting bullets when auto-wrapping.
Add preferred style guide to CONTRIBUTING.
Typos in CONTRIBUTING.
Merge pull request #76 from cirosantilli/master

Typos in CONTRIBUTING.
Add flag to disable/enable bookmark sorting

The bookmarks are normally sorted, however with a newly introduced
flag this can be disabled.
Fix curl command to support GitHub's new redirect

Closes #120.
add ack version on readme(fixes #125)