This PR is part of porting all old scripts #221 and includes the
`virtual_environments` module
## 5 files changed
- `conda.nu`: removed, already in
`modules/virtual_enviromnents/conda/nu_conda.nu`
- `conda_deactivate.nu`: also removed, has already been merged with
`nu_conda.nu`
- `README.nu`: removed, similar info in
`modules/virtual_enviromnents/README.md`
- `venv.nu`: ported to `modules/virtual_enviromnents/venv/venv.nu`
- `venv_deactivate.nu`: ported to
`modules/virtual_enviromnents/venv/venv_deactivate.nu`
