Add counters on detail pages

[Gsantomaggio]

closes #3416

Proposed Changes

Add counters on detail pages

Types of Changes

• Bug fix (non-breaking change which fixes issue #NNNN)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause an observable behavior change in existing systems)
• Documentation improvements (corrections, new content, etc)
• Cosmetic change (whitespace, formatting, etc)

Checklist

• I have read the CONTRIBUTING.md document
• I have signed the CA (see https://cla.pivotal.io/sign/rabbitmq)
• I have added tests that prove my fix is effective or that my feature works
• All tests pass locally with my changes
• If relevant, I have added necessary documentation to https://github.com/rabbitmq/rabbitmq-website
• If relevant, I have added this change to the first version(s) in release-notes that I expect to introduce it

Further Comments

@acogoluegnes for the stream.js I could not use the .ejs script to count the items.
I used the standard java script way

an example

[pjk25]

@Gsantomaggio should this backport to 3.9 and 3.8?

[michaelklishin]

@pjk25 it modifies a 3.9-specific file, I think we can keep it to v3.9.x