Handle release parameter more sensibly in force manifest.

Use release parameter to construct $release_string.

The release parameter may also be set to false to use the system's
default release (so just force a specific version). Use false as the
default setting instead of 'testing'.

Change $install_check to also check if package is installed from the
right release, instead of just checking the version.
Don't use hardcoded provider in force manifest.

Use $apt::params::provider instead.
Update specs to test all parameter cases
Update example apt::force tests
Add wheezy backports support

Signed-off-by: Markus Rekkenbeil <markus@bionix-it.de>
Use the geoDNS http.debian.net instead of the main debian ftp server

Signed-off-by: Markus Rekkenbeil <markus@bionix-it.de>
Update specs for #145
Merge pull request #151 from hunner/proxy_exec_spec

Update specs for #145
Merge pull request #149 from bionix/add_wheezy_backports

Add wheezy backports support
Merge pull request #150 from bionix/use_http_debian_net_as_geodns_redirector

Use the geoDNS http.debian.net instead of the main debian ftp server
Fixed several lint warnings and errors
removing unnecessary backslashes
Merge pull request #156 from rculbertson/master

Fixed several lint warnings and errors
Added class for managing unattended-upgrades
Added spec test for unattended-upgrades class
[#153] Rename unattended_upgrades s/-/_/

It's preferable to use underscores rather than hyphens in class names. Refs:

- http://projects.puppetlabs.com/issues/5268
- http://docs.puppetlabs.com/puppet/3/reference/lang_reserved.html#classes-and-types
[#153] Convert t/f params to bools and validate

Per lint check: http://puppet-lint.com/checks/quoted_booleans/
[#153] Variablise file paths in unattended spec

Reduce some duplication of long file paths.
[#153] Test defaults for some unattended params

For params which have any logic embedded in the template:

- origins
- blacklist
- mail_to
- dl_limit
[#153] Install unattended configs after package

To ensure that the default configs from the package are always overwritten
within a single Puppet run.