(PDB-954) Support a fallback database

This commit moves from a combo 'server' and 'port' config to a
'server_urls' config that contains the full path to one or more PuppetDB
URLs. The old server/port format is still supported (internally it is
converted to a URL to conform with the new syntax).

This commit also supports a new 'server_url_timeout' config. If the
PuppetDB instance has responded in the specified number of
seconds (defaults to 30) it will fail and roll to the next PuppetDB
url (if one is provided).
Merge pull request #1129 from wkalt/ticket/master/pdb-954-fallback-acceptance

Ticket/master/pdb 954 fallback acceptance
Switching RPM/DEB package to use globbing on terminus directories
Merge pull request #1131 from senior/ticket/master/pdb-100-packaging-for-new-rb-files

Switching RPM/DEB package to use globbing on terminus directories
(maint) fix broken package tests

This updates the install_puppetdb_termini function called during package
acceptance tests to use server_urls
Merge pull request #1133 from wkalt/maint/fix-fallback-pkg-test

(maint) fix broken package tests
DOCUMENT-211: Switched greater than / less than operators

The greater than or equal to (>=) and less than or equal to (<=) signs were swapped. Now they aren't.
Merge pull request #1136 from jbondpdx/docfix

DOCUMENT-211: Greater than or equal to and less than or equal to swapped
Merge branch 'stable'

* stable:
  DOCUMENT-211: Switched greater than / less than operators