Can't turn off deprecation warnings

There are a few different issues with how warn_once is implemented that prevent deprecation warnings from being silenced.

1. There are typos, e.g. deprecatation
2. We use both symbols and strings:

   Puppet.warn_once('deprecation', 'AST::ResourceParam', _('Use of Puppet::Parser::AST::ResourceParam is deprecated and not fully functional'))

   Puppet.warn_once(:deprecation, "metadata.json#data_provider-#{module_name}",

3. The warn_once logic doesn't account for string vs symbol, which probably wasn't a problem before we removed the symbol string monkey_patch:

   return if Puppet[:disable_warnings].include?(kind)

4. The disable_warnings setting only accepts plural deprecations, but all of the warn_once call sites use singular deprecation, so the include? check never matches
5. There is another warnonce method defined in Puppet::Util::Warnings.

But the main issue is that you can't turn deprecations off:

notify { '1':

  message => strftime("%s")

}

notify { '2':

  message => strftime("%s")

}

$ bundle exec puppet apply warnings.pp --disable_warnings deprecations

/Users/josh/work/puppet/.bundle/ruby/2.4.0/gems/CFPropertyList-2.2.8/lib/cfpropertylist/rbCFTypes.rb:24: warning: constant ::Fixnum is deprecated

Warning: The argument signature (String format, [String timezone]) is deprecated for #strfime. See #strftime documentation and Timespan type for more info

   (file & line not available)

Notice: Compiled catalog for chara.corp.puppetlabs.net in environment production in 0.02 seconds

Notice: 1496267306

Notice: /Stage[main]/Main/Notify[1]/message: defined 'message' as '1496267306'

Notice: 1496267306

Notice: /Stage[main]/Main/Notify[2]/message: defined 'message' as '1496267306'

Notice: 1496267306