(PDB-3318) Better defaults for node-ttl, node-purge-ttl

[mullr]

Default node-ttl to 7 days and node-purge-ttl to 14 days. This helps keep cruft
from piling up in the database in the default configuration, without user
intervention.

[puppetlabs-jenkins]

Test PASSed

[mullr]

@senior looks like you were right, in the module we explicitly default these things:

  # These settings manage the various auto-deactivation and auto-purge settings
  $node_ttl               = '0s'
  $node_purge_ttl         = '0s'
  $report_ttl             = '14d'

[mullr]

puppetlabs/puppetlabs-puppetdb#254

[puppetcla]

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