chore(*): Added editorconfig

editorconfig configures editors to use the correct indent size and
style.

Replaces #2347
At lot of shell scripts use just two spaces: https://www.dropbox.com/s/t5g9xayvv7sd8mh/Screenshot%202014-11-06%2012.02.42.png?dl=0 and they don't have a filterable extension, so either the default shell indentation should be 4 spaces or we need to add rst separately.