This module behaves exactly the same as 'Module::Pluggable', supporting all
of its options, but also mixes in the 'call_plugins' and 'plugins_ordered'
methods to your class. 'call_plugins' acts a little like 'Class::Trigger';
it takes the name of a method, and some parameters. Let's say we call it
like so:

__PACKAGE__->call_plugins("my_method", @something);

'call_plugins' looks at the plugin modules found using 'Module::Pluggable'
for ones which provide 'my_method_order'. It sorts the modules numerically
based on the result of this method, and then calls
'$_->my_method(@something)' on them in order. This produces an effect a
little like the System V init process, where files can specify where in the
init sequence they want to be called.