Add a &reverse_method_lookup to MooseX::AttributeHelpers::Base which 
given a name of a providable method will return the method name chosen
by the consumer of the module. Something like this.

has +method => (default => sub {
    return +{
        'foo' => sub {
            my ($attr, $reader, $writer) = @_;
            my $bar_method_name = $attr->reverse_method_lookup('bar');
            return sub {
                $_[0]->$bar_method_name()
            }
        },
        'bar' => sub {
           ...
        }
    }
})