(PE-437) Update Dependencies to reflect new pe-puppet package

On debian we have unified the pe-puppet packages to match the red hat packages,
e.g. into a pe-puppet-server package and pe-puppet package. pe-puppet-agent no
longer exists, nor does pe-puppet-common. This commit updates the debian
requirements for pe-puppetdb to correctly reference pe-puppet package instead
of pe-puppet-agent or pe-puppet-common.

Signed-off-by: Moses Mendoza <moses@puppetlabs.com>
Merge pull request #522 from MosesMendoza/maint/master/update_requires_for_new_puppet

(PE-437) Update Dependencies to reflect new pe-puppet package