(#51) Add option to disable SSL in Jetty

This patch introduces the optional parameter $disable_ssl, which
defaults to false. If set to true, the settings ssl-host and ssl-port
are completely removed from the Jetty section of the PuppetDB config
files.

This disables serving of HTTPS requests by PuppetDB, which can be useful
when SSL handling is offloaded to a reverse proxy server like Apache or
Nginx, as suggested in the PuppetDB documentation (see
http://docs.puppetlabs.com/puppetdb/1.2/connect_puppet_apply.html#option-a-set-up-an-ssl-proxy-for-puppetdb).
Merge branch 'master' into feature/master/option_to_disable_ssl
Remove trailing whitespace
Merge branch 'feature/master/jetty_ini_tests' into feature/master/option_to_disable_ssl
Add unit tests for disabling SSL in puppetdb::server::jetty_ini
Ruby 1.8.7 doesn't like a comma after the last hash entry.
Merge branch 'master' into feature/master/option_to_disable_ssl
Document new option disable_ssl in README.
Merge pull request #52 from christianberg/feature/master/option_to_disable_ssl

Add option to disable SSL in Jetty