Add Centos 7 acceptance tests

This includes a new test AMI for Centos 7 to test against.

Signed-off-by: Ken Barber <ken@bob.sh>
(PDB-653) metrics update on PDB start

Previously the DLO metrics only updated on a failed command submission, which
meant restarting PDB would blank the metrics until the next failure. This patch
initializes DLO metrics on PDB startup if the DLO directory, which is created
on first failure, already exists.
Update release notes for PDB 2.2.1 release.
Merge pull request #1119 from wkalt/2.2.1-release-notes

Update release notes for PDB 2.2.1 release.
Merge pull request #1116 from kbarber/maint/stable/centos-7-testing

Add Centos 7 acceptance tests
(PDB-952) Include packaging detection for centos 7

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #1121 from kbarber/maint/stable/pdb-952-fix-for-el7-packaging

(PDB-952) Include packaging detection for centos 7
Upgrade distros to ensure all packages are the latest

Without this we are seeing elements fall behind, such as the new SSL changes
to the EPEL mirror which are no longer compatible with the SSL setup on older
RHEL6/7 boxes.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #1123 from kbarber/maint/stable/upgrade-test-distros

Upgrade distros to ensure all packages are the latest
(PDB-964) Switch to using curl --tlsv1 everywhere

This works around the problems where sites are dropping SSLv3
support so our tests continue to work.

Signed-off-by: Ken Barber <ken@bob.sh>
(PDB-962) Remove SSLv3 as a default from Jetty config

If the user doesn't specify `ssl-protocols` we should no longer default
to SSLv3 as it has known vulnerabilities. This commit changes the
default to be the TLS protocols. If the user has specified SSLv3, this
is allowed, but the user will be warned.
Updated docs to include --tlsv1 in all https curl examples
Merge pull request #1125 from kbarber/ticket/stable/pdb-964-switch-curl-to-force-tlsv1

(PDB-964) Switch to using curl --tlsv1 everywhere
Merge pull request #1126 from senior/ticket/stable/pdb-962-sslv3-defaults

(PDB-962) Remove SSLv3 as a default from Jetty config
Merge branch 'stable' into maint/master/rollup-from-stable

* stable:
  Updated docs to include --tlsv1 in all https curl examples
  (PDB-962) Remove SSLv3 as a default from Jetty config
  (PDB-964) Switch to using curl --tlsv1 everywhere
  Upgrade distros to ensure all packages are the latest
  (PDB-952) Include packaging detection for centos 7
  Update release notes for PDB 2.2.1 release.
  (PDB-653) metrics update on PDB start
  Add Centos 7 acceptance tests

Conflicts:
	src/puppetlabs/puppetdb/cli/services.clj
	src/puppetlabs/puppetdb/config.clj
	test/puppetlabs/puppetdb/config_test.clj
Correct the ssl-protocols rewrite for the master branch

Right now tk-webserver-jetty9 0.7.5 requires a list to be passed to it for
the setting `ssl-protocols` but our rewrite still provides a comma separated
string.

While this is a bug in-and-of-itself, its causing our tests to fail. This
patch gets us back to passing. We'll look at the configuration issue as a
part of the fixes going into TK that might resolve this.

Signed-off-by: Ken Barber <ken@bob.sh>
Merge pull request #1127 from kbarber/maint/master/correct-ssl-protocols-rewrite-to-suit-later-tk

Correct the ssl-protocols rewrite for the master branch
(PDB-100) Change the terminus to support multiple (failover) PuppetDB URLs

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). In the event the
user has more than one URL specified and there is an error, such as
connection refused, or a 503 response, the terminus will not attempt the
next PupppetDB URL specified in the 'server_urls' list.

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).