Add Base#info_all method to iterate through all available queues...

... and get their details

Will be used in [this PR](https://github.com/Shopify/q2/pull/292) to get the queue sizes and wait times for each queue.

In phones we'll have to loop through all tasks for each queue, get the oldest timestamp to calculate the wait time for that queue (with call transfers the oldest task might not be at the top).

@tylermercier @odorcicd