allow to pass an (optional) username to the connection helper

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
add a global option to allow a different username

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
get_connection now will construct the username and host for you

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
install now uses the new username flag!

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
bump the remoto version

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
use the new args.username to get the connection

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
update the docs with the new flag

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
remove TODOs related to usernames

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
missing refactoring call to hosts.get

Signed-off-by: Alfredo Deza <alfredo.deza@inktank.com>
Merge pull request #109 from alfredodeza/3347

allows a user to pass in `--username` for connecting to remote hosts