rfc: Support for stronger ssh key exchange
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With `openssh` [6.5](http://www.openssh.com/txt/release-6.5) the support for `Ed25519` as public key type was added.
gitlab.com supports private/public key exchange with this [elliptic curve](https://en.wikipedia.org/wiki/Curve25519) released by Daniel J. Bernstein. I would really like to extend the existing "generate ssh key" manual/documentation site with:
```bash
ssh-keygen -t ed25519 -C "name@domain.com" -f gitlab
```
In [this](https://stribika.github.io/2015/01/04/secure-secure-shell.html) article about "securing the secure shell" I adopted one possible config entry for the ssh `config` (normally located in `~/.ssh/config`):
```
Host gitlab.com
HostName 104.210.2.228
AddressFamily inet
KexAlgorithms curve25519-sha256@libssh.org
HostKeyAlgorithms ssh-ed25519
Ciphers chacha20-poly1305@openssh.com
IdentityFile ~/.ssh/gitlab
User git
```
This example is based on the gitlab.com credentials.
So do you think it is worth to have these kind of suggestions shown on the offical `help/ssh/README` guide?
issue