add an 'ensure' parameter to apt::ppa

...as sometimes we want to get rid of them. :)

We leave this a little loose; rather than simply requiring a boolean for
$ensure, we set the stage for doing an easy switch to also allowing 'purge' at
some point in the future.
Retry package installs

Sometimes package installs can fail to aquire the lock file, so retry
the command in that case.
Merge pull request #185 from dalen/retry

Retry package installs
Merge pull request #184 from RsrchBoy/topic/removable-ppas

add an 'ensure' parameter to apt::ppa
Correct spelling typo in CHANGELOG
Use include instead of parameterized class when no params are given.

Instead of perpetuating the use of parameterized classes, which we do
not want to do in light of Puppet v3 with Hiera integration, this change
invites people to use 'include' instead of the parameterized class
syntax when no params are present.
escape more braces properly

Fixes a couple of rspec regex warnings.
Fix the name of sources.list.d file resource in apt::ppa
Merge pull request #191 from mnencia/patch-1

Update ppa.pp
Merge pull request #188 from sd63/fix_regex_warning

escape more braces properly
Merge pull request #187 from ghoneycutt/style_for_class_with_no_params

Use include instead of parameterized class when no params are given.
Merge pull request #186 from ghoneycutt/typos

Correct spelling typo in CHANGELOG
change include_class to contain_class in specs

include_class was deprecated starting from rspec-puppet 1.0.0.
Merge pull request #195 from sd63/include_class-deprecated

fix deprecation warning with rspec-puppet 1.0.0 (and newer)
(#201) Use root to exec

User root is needed to execute this command.

If someone changes the default Exec user, apt-add-repository will fail.
Change - to _

I did it to please my syntax validator, but I'm assuming it wasn't functioning as expected either.
Merge pull request #205 from braddeicide/master

fixed include, contained dash instead of underline.
Merge pull request #202 from tsuharesu/bug/exec_apt_ppa_as_root

Apt::ppa should exec with root
Convert existing tests over to beakr-rspec.
Merge pull request #206 from apenney/beaker-rspec

Convert existing tests over to beakr-rspec.