Add .editorconfig
editorconfig.org is a project to help maintaining consistency between editors and developers. The community is largely relying on this to keep up consistency in some coding styles (I used it myself professionally too).
This PR adds this confiiguration file. I've created the configuration in the file by observing the code styles in your files. So it is not a reflect of my coding preferences. To use it, you'll need to add the required plugiin to the editor of your choice, mostly every code editor is supported. Eventually it would be needed to add a Developers section in the readme.
You can always adapt or change it. Or ask me to change something in this config before you merge it, of course.