bug#20322: 25.0.50; indent-tabs-mode should default to nil

[Dmitry Gutov]

Here's another recent analysis:

http://ukupat.github.io/tabs-or-spaces/

It's different from the previous ones in certain aspects:

- Analyses XX most popular GitHub repositories for a given language.

- Counts percentage of repositories using a given style, not files.

- Uses the algorithm that looks at the lines where indentation changes 
(https://github.com/sindresorhus/detect-indent/), mostly to distinguish 
between different offsets in spaces-based indentation.

https://github.com/ukupat/tabs-or-spaces