When consumer is paused check if it's paused

Description
===========
Feature request. When pausing a consumer, it would be nice if there was a way to check if the consumer is paused. For example a consumer could be paused / resumed based on various conditions and the user may want to know the current state of the consumer. Currently the only way to do this would be to store the state externally in another variable.

How to reproduce
================
```
from confluent_kafka import Consumer

c = Consumer({...})
c.subscribe(topics)
c.pause(topic_partitions)
# how to check if the consumer is paused?
```

Ideally the consumer would have a method like `.is_consumer_paused()` or a property `.paused`