Move language bindings to the top level directory

## Brief

Currently the C, C++ and Python bindings are located in the `iceoryx2-ffi` folder as `c`, cxx` and `python`.

They should be placed at the top level directory, with only the Rust FFI crates in `iceoryx2-ffi`.

## Action items

* [x] move `iceoryx2-ffi/c` to `iceoryx2-c`
* [x] move `iceoryx2-ffi/cxx` to `iceoryx2-cxx`
* [x] rename `iceoryx2-ffi/ffi` to `iceoryx2-ffi/c` once that name is available
* [ ] move `iceoryx2-ffi/python/python-src` to `iceoryx2-python`
* this is a bit more tricky, since a symlink to `iceoryx2-ffi/python/python-src` needs to be created
* if the setup with the symlink does not work, the Pythen bindings will remain in `iceoryx2-ffi/python/python-src`

Review the merged pull request #966 and inspect the current repository layout, especially iceoryx2-ffi/python/python-src and the top-level binding directories. Verify whether the Python binding move and symlink still remain; done means the C, C++ and Python bindings are at the top level while iceoryx2-ffi contains only Rust FFI crates.

Written by the indexing model from the issue text.