With the introduction of an external project reference via git submodule by `tls_wolfssl`, I am opening this to discuss where it would be the _best_ place for them.

Now it is in the folder of the tls_wolfssl module, but I noticed that many projects have a dedicated folder like `vendor` (or `extern`, `import`), and I would somehow that approach more because it is easier to locate the external code and figure out its implications in licensing, dependencies, etc ...

Moreover, it can happen that many modules would need to use that external project/repo. For example, now crypto uses libssl, but for someone that wants to get rid of it and use only libwolfssl may contribute an alternative of that module. Then two modules would need same external repo and having it inside another module would not be straightforward to manage.

Given the above, I would suggest to place them in a folder like `misc/vendor` or similar inside the `misc/` directory, not to get back into growing the root folder. I would like to keep `src/` folder only for Kamailio specific code.

If someone has other suggestions, propose them in comments and let's try to get to a decision soon.