Busser config key name is `sudo` not `use_sudo`
Ensure `busser/ruby_bindir` config value is respected
Ensure `busser/busser_bin` config value is respected
Remove all newline characters from remote Busser commands

Some shells (*cough* C shell *cough*) do not appreciate commands 
littered with newline characters. This commit just ensures all remote 
Busser commands are one liners. Even though the remote Busser commands 
are executed under Bourne (via `sh -c`) we cannot guarantee the $SHELL 
of the user we are SSH-ing in as will be Bourne.

More info regarding C shell (csh) + newlines here:
http://www.grymoire.com/Unix/CshTop10.txt
Update string quoting style in Busser#sync_cmd.
Convert Busser config to use a #config Hash, like Provisioner & Driver.

This should allow for more consistent configuration output and pave the
way for user, default, inherited, and computed configuration support.
Remove dead code in Busser, yay.
Set `Busser[:sudo]` to `false` by default.
Merge pull request #265 from test-kitchen/busser-fixes

Busser Fixes for Greybeard UNIX