Add AMQP queue declaration configuration options

[julianwachholz]

This allows setting additional arguments for AMQP queue declaration.
For example with RabbitMQ this will let you use Priority Queues by setting a x-max-priority on the queue and using x-priority headers on messages.

[codecov]

Codecov Report

Merging #428 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff            @@
##           master    #428      +/-   ##
=========================================
- Coverage   47.91%   47.9%   -0.02%     
=========================================
  Files          29      29              
  Lines        2642    2643       +1     
=========================================
  Hits         1266    1266              
- Misses       1237    1238       +1     
  Partials      139     139

Impacted Files	Coverage Δ
v1/config/config.go	80% <ø> (ø)	⬆️
v1/tasks/signature.go	41.17% <ø> (ø)	⬆️
v1/brokers/amqp/amqp.go	4.16% <0%> (-0.02%)	⬇️

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[julianwachholz]

@RichardKnop I'm not sure how to add more coverage here? Is it okay to merge?

[pmengcv]

there has another problem
#825