Windows-related patches, and a couple util patches

[LunarWatcher]

Problems (theoretically) fixed:

• Opening a file from NERDTree that exists on a different server destroys the NERDTree buffer and breaks :NERDTreeToggle. If relevant, closes splits (including intended persistent ones)
  • Patch: Call bp before deleting the buffer (https://stackoverflow.com/a/4403691).
• Doesn't work with deep paths (SomeFile.txt is fine, D:\some\path\SomeFile.txt is not) - Windows only
  • Patch: Flipping quotes (https://stackoverflow.com/a/32067073)
• Window change doesn't doesn't focus on Windows
  • Patch: Call remote_foreground() instead of foreground() on Windows. See :help foreground(): "On Win32 systems this might not work, the OS does not always allow a window to bring itself to the foreground.". remote_foreground() (:help remote_foreground()) is called on Windows because it brings focus to a non-minimized window. From my testing, both are required. Gotta love Windows.
• The script some times claims there's a recursive swap when there isn't
  • Patch: flip s:in_remote_open to 0 instead of 1 on line 43 (previously line 41). Might be a typo?

[codeape2]

LGTM