Include thirdparty libraries as submodules

[feliwir]

Hello,
would it be welcome if i include thirdparty libraries as submodules?
It makes managing & versioning a lot simpler and reduces the overall size of the repository. Of course this is only viable if there weren't any customizations done to the libraries.

Most projects (in their unmodified form) can just be compiled by using add_subdirectory - this would probably require updating a few of the dependencies.

[autious]

There's already a discussion related to this here #15, i suggest adding to that discussion.

[Conan-Kudo]

Duplicates #15

[Conan-Kudo]

Duplicate of #15