initial implementation of the ssh package including:
- nativeConnectionCreate() / golangConnectionCreate()
- n/a / golangConnectionDial()
- nativeConnectionScp() / golangConnectionScp()
- nativeConnectionExec() / golangConnectionExeC()
the way this works, is there are publicly accessible functions Create, Exec, Dial and Scp. podman will have a new global flag --ssh` that will allow users to choose native or golang based ssh functions. The functionality in containers/common (here) also checks if you have the necessary binaries installed
closes#1091
Signed-off-by: Charlie Doern <cdoern@redhat.com>