YCP Killer: Unify YaST module structure

The existing directory tree layout of YaST modules wasn't consistent
across modules and it was different from the layout used after
installation. We decided to unify it to fit a regular structure. This
commit does so for this module.

The commit is a result of running YCP Killer's "restructure" command.

See also:

  https://github.com/yast/ycp-killer#new-yast-module-structure
  https://github.com/yast/ycp-killer
YCP Killer: Apply changes needed for Ruby translation

This module needed few changes before it was possible to translate its
YCP files into Ruby. This commit performs them.

The commit is a result of running YCP Killer's "patch" command. The
history of the applied patch is available here:

  https://github.com/yast/ycp-killer/commits/master/patches/mail.patch

See also:

  https://github.com/yast/ycp-killer
YCP Killer: Translate YCP files into Ruby

The commit is a result of running YCP Killer's "ruby" command.

See also:

  https://github.com/yast/ycp-killer
YCP Killer: Regenerate Makefile.am files in all source directories

The commit is a result of running YCP Killer's "makefile" command.

See also:

  https://github.com/yast/ycp-killer