support ssh deployment

[marco-brandizi]

I cannot find if this is already available, or a feature request exists, sorry for possible duplicates.
As it appears from other tickets, the GH/maven-site plug-in isn't able to upload a file >25MB, due to limits that GH has over web-based updates. I get that this includes the APIs that the plugin is using.

Wouldn't it be possible to support SSH-based interaction with GH? Maybe via Wagon? This way it would be possible to upload files of up to 100Mb.

A possibly better alternative could be supporting Git-LSF. it might be the case that this can be done via Maven configuration only without any need to change the code for the site plug-in. In that case, some documentation and examples would help a lot.