Update RabbitTemplateConfigurer to take its required settings as constructor arguments

[wilkinsona]

RabbitTemplateConfigurer has three settings:

• messageConverter
• retryTemplateCustomizers
• rabbitProperties

rabbitProperties must be set but both messageConverter and retryTemplateCustomizer are optional. All three are configured via setter methods making it hard to distinguish between things that are required and things that are optional. As it's required, it'd be good if rabbitProperties was a constructor parameter.

To do this in a backwards-compatible manner we'll have to keep the default constructor and add one that takes a RabbitProperties instance alongside it. We'll also have to keep the setter, albeit in a deprecated form.

[beatfreaker]

@wilkinsona is this issue open for contribution ? can I work on it ?

[wilkinsona]

Thanks for the offer, @beatfreaker, but as indicated by its assignment to me, I'm already working on it.