Installation is now working

usage:

cyg.installed:
    - names:
      - dos2unix
      - ssh
      - vim
      - tmux

Some of you may notice that 'ssh' is not a cygwin package, 'openssh' is. Currently it is reported as successfully installed. My next step is to check the list of named packages against the available packages and return false if they don't exist.

Have not tested package removal.