Fix minor indentation issues and track dub lock file

[ljmf00]

I'm currently planing doing some extra unittests to cover some reported issues on D modules and found that I committed some spaces instead of tabs.

Also, dub.selections.json should be tracked by git as it is a lock file for versions described on dub.json. Although, we don't have any dependencies here nor doing version pinning and the dub.selections.json is almost empty, it's a good practice to have it there.

e.g.: See the official repository, https://github.com/dlang/dub

[ljmf00]

@jpakkane tagging here, due to be a very calm project.

[jpakkane]

Tabs are actually wrong, everything in Meson should be space-indented.

[ljmf00]

Tabs are actually wrong, everything in Meson should be space-indented.

Ok, then I changed everything to spaces. I also added .editorconfig to match some settings from meson repository and *.d files with 4 spaces of indentation.

[ljmf00]

When everything is good to go, after merge it, please consider creating a new version tag, matching the same syntax of D version tagging to trigger dub registry. It will publish the missing test3 subproject.

[jpakkane]

What should be the correct name for the tag? The existing one seems to be v1.0.0 but everywhere on the Dub site it is called just 1.0.0. v1.1.0?

[ljmf00]

You should tag with a v prefixed. Like you just said: v1.1.0, but on dub registry it will appear just 1.1.0