Use .editorconfig to prevent tab and space mixed

[vanduc1102]

Changes

This pull request makes the following changes:

• Use editorCongfig to prevent tab and space mixed
• The config is origin from https://github.com/laravel/laravel/blob/master/.editorconfig , I changed space to tab

Why

For #

Testing/Questions

Features that this PR affects:

Questions that need to be answered before merging:

• Is this PR targeting the correct branch in this repository?
• [ ]

Steps to test this PR:

Additional information

INN Member/Labs Client requesting: (if applicable)

• [x ] Contributor has read INN's GitHub code of conduct
• [x ] Contributor would like to be mentioned in the release notes as: (fill in this blank)
• [ x] Contributor agrees to the license terms of this repository.

[benlk]

If we're going to have an editorconfig in this repository, it needs to match WordPress' code styles for PHP code and INN's own code styles: https://github.com/INN/docs/tree/master/style-guides/code

We'll also need to add guidance to our documentation in Largo and in INN/docs regarding where to learn more about getting editorconfig support for your text editor.

[benlk]

https://github.com/WordPress/wordpress-develop/blob/master/.editorconfig is WordPress Core's editorconfig.

[vanduc1102]

Hi @benlk , i updated the .editorconfig to https://raw.githubusercontent.com/WordPress/wordpress-develop/master/.editorconfig

for documentation updating, I'm afraid i cant do it with my current English level