Add 'exclude' as an option for rsync::server::module

There was no exclude param, so I've added one. Needed for some work internally.
Fix missing newline-chomp in rsync::server::module template

The missing `-` on line 25 was injecting a newline for any entries
after `@auth_users`. Just throwing it back in there.
Add Debian support (based on PR 22, by splebel)

This adds a /etc/defaults/rsync file for Debian based systems,
as well as adjusts the appropriate filenames for out-of-the-box
usage on Debian systems.
Clean up Debian patches

The original pull request for Debian support was a little old,
so some of the coding conventions have been cleaned up a little bit:
case sentivity, selectors instead of case statements, etc.

Also included a requirement on puppetlabs/stdlib in order to
use the function str2bool, which is handy.
Merge pull request #29 from mckern/exclude_all_the_things

Exclude all the things!