Add support for newer ssh key types

[kylechase]

Github has removed for rsa-sha1 keys, which seems to be the only key type supported in the module currently. I think we can swap Jsch for https://github.com/mwiede/jsch, which adds support for newer keys. I will take a look.

[AXONE-IO]

Hello @kylechase,

You can currently use a PEM key.
ssh-keygen -m PEM -t ecdsa -b 521 -C "your.emailadress@gmail.com"

https://www.axone-io.com/Files/Modules/GIT/1.0.0/doc/index.html#Generate-SSH-key

I will take a look at your proposal.

[kylechase]

Thanks, I managed to get a ECDSA key to work.