When searching for root line num, stop at the end of the file.

[PhilRunninger]

When using the following NERDTreeStatusLine, Vim would lock up and not
work anymore. The problem was that when trying to find the root line
number, the loop was continuing past the end of the file, looping
"forever". The fix was to simply stop at the end of the file.

let g:NERDTreeStatusline = "%{exists('g:NERDTreeFileNode')&&" .
\ "has_key(g:NERDTreeFileNode.GetSelected(),'path')?" .
\ "g:NERDTreeFileNode.GetSelected().path.getLastPathComponent(0):''}"

Description of Changes

Closes #467

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New Version Info

• Derive a new version number. Increment the:
  • MAJOR version when you make incompatible API changes
  • MINOR version when you add functionality in a backwards-compatible manner
  • PATCH version when you make backwards-compatible bug fixes
• Update CHANGELOG.md, following this format/example:

  #### MAJOR.MINOR...
  - **.PATCH**: PR Title (Author) #PR Number
  
  #### 5.1...
  - **.1**: Update Changelog and create PR Template (PhilRunninger) #1007
  - **.0**: Too many changes for one patch...