This adds split explorer capability to NERDTree

[tempoz]

Description of Changes

This adds a g:NERDTreeSplexMode boolean setting that, when activated, causes NERDTree to act as split explorer-style file browser instead of a project drawer.

Motivation for Changes

I was looking for a way to browse my filesystem in vim and I came across NERDTree, which I love the look and feel of, but in my search I had also come across many articles extolling the virtues of split explorer-style browsers. Given my restricted monitor space and preference for more intuitive window-splitting, I decided to try to do both. I understand entirely if the project maintainers do not wish to support this feature, but since I'd gone to the trouble of developing it, I thought I'd offer it up.

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New Version Info

Author's Instructions

• Derive a new MAJOR.MINOR.PATCH 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 the established pattern.

Collaborator's Instructions

• Review CHANGELOG.md, suggesting a different version number if necessary.
• After merging, tag the commit using these (Mac-compatible) bash commands:

  git checkout master
  git pull
  sed -n "$(grep -n -m2 '####' CHANGELOG.md | cut -f1 -d: | sed 'N;s/\n/,/')p" CHANGELOG.md | sed '$d'
  git tag -a $(read -p "Tag Name: " tag;echo $tag) -m"$(git show --quiet --pretty=%s)";git push origin --tags

[PhilRunninger]

@tempoz This is a nice idea, but I'd rather see this done with a new command, instead of adding more settings. This will give the users the ability to more easily choose between the drawer style and the explorer style. Can you rework it with that in mind?

[tempoz]

Sure! It may take me a little time to get the chance to work on it again, but I don't think it will be too difficult to swap from this style to a command style.

[rzvxa]

Hey @tempoz,

I'm going to close this PR since with #1389 we have a similar feature that essentially provides the same functionality which as a result makes this PR obsolete.
I really appreciate this great work; Even tho it didn't make it to the NERDTree codebase, The initial idea was really useful and I just want to thank you on behalf of everyone who uses this plugin and especially this new feature.

I wish you a lot of happiness wherever you are!

Have a great day!