package.json: set ssh2 dependency to ^0.5 to enable ECDSA/ECDH support

[Darkspirit]

https://github.com/mscdex/ssh2/wiki/Changes-from-0.4.x-to-0.5.x

• Support for ECDH for key exchange (node v0.12+).
• Support for ECDSA keys (both for server host keys and private keys for user authentication) (node v5.2.0+).

In our /etc/ssh/sshd_config (OpenSSH on Ubuntu 16.04 server) we have:
HostKey /etc/ssh/ssh_host_ecdsa_key
# generated with ssh-keygen -t ecdsa -b 521 -N "" -o -f /etc/ssh/ssh_host_ecdsa_key

KexAlgorithms ecdh-sha2-nistp521
Ciphers aes256-gcm@openssh.com,chacha20-poly1305@openssh.com
MACs hmac-sha2-512-etm@openssh.com

[Darkspirit]

But #325 could be still a problem. (I don't know.)

(Only) With the latest stable Atom, I am able to connect to my server, if
i change ssh2 to "^0.5" in ~/.atom/packages/Remote-FTP/package.json,
run "apm install" in that folder (to load ssh2 0.5.0),
set hosthash to sha1 in .ftpconfig,
and change my sshd_config to "MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-512".

I tried to set ssh2 to *, but then "apm install" wont load anything (=no 0.5.0)

Atom : 1.9.8
Electron: 0.37.8
Chrome : 49.0.2623.75
Node : 5.10.0

[jimmaaay]

Hey I'll have a look and see what I can do.

[jimmaaay]

Just to let you know it may take a while as I will need to setup some tests to make sure that this does not recreate the issue #325

[jimmaaay]

@terrax-net This should work now in 0.9.2. As ssh2 has dependency has been set to ^0.5